By Peter Hessler

A few days before my return to classroom teaching at Sichuan University, I was biking across a deserted stretch of campus when I encountered a robot. The blocky machine stood about chest-high, on four wheels, not quite as long as a golf cart. In front was a T-shaped device that appeared to be some kind of sensor. The robot rolled past me, its electric motor humming. I turned around and tailed the thing at a distance of fifteen feet.

It was May 27th, and it had been more than three months since my last visit to the university’s Jiang’an campus, which is on the outskirts of Chengdu, in southwestern China. In late February, when the spring semester was about to begin, I had hurried to campus to retrieve some materials from my office. We were nearly a month into a nationwide lockdown in response to the coronavirus, which had started in Wuhan, a city about seven hundred miles east of Chengdu. The university had informed the faculty that, at least at the beginning of the term, all courses would be online.

In those days, it still seemed possible to escape the disease by leaving China, and a number of foreign teachers at the university had departed. At the U.S. Embassy and consulates, nonessential staff had been evacuated, along with the spouses and children of the diplomats who remained. Throughout February, I answered e-mails from worried friends and relatives in the U.S. I reassured them that my family was fine, and told them that we had decided to stay in Chengdu, despite numbers that, at least at that particular moment, seemed frightening. On February 20th, when I visited campus, China’s official death toll reached 2,236.

Since then, the semester had crawled along, as everybody’s perspective on the disease changed. During the third week of classes, the epidemic officially became a pandemic; by week six, the U.S. death toll had exceeded that of China. That week, China’s borders were closed to foreigners, and the evacuations reversed direction—Chinese nationals in America and Europe, many of them students, were desperately trying to return home. China was the first to experience the pandemic, and it was also among the earliest countries to control the spread and enter what would now be considered normal life. In week eleven, my nine-year-old twin daughters resumed classes; in week thirteen, I boarded a plane for the first time in the post-coronavirus era. And now, on May 27th—week fourteen—I was finally back on campus.

I followed the robot until it paused on a street lined with dormitories. An electronic voice called out, “Daoda zhandian! ”—“Arriving at the stop!” The street was empty, because most undergraduates hadn’t yet returned. One new policy was that students couldn’t leave after entering campus, unless they received special permission. Every gate to the university had been equipped with facial-recognition scanners, which were calibrated for face coverings. Earlier that day, when I arrived, a guard told me to keep my mask on while being scanned. My name popped up on a screen, along with my body temperature and my university I.D. number. As a faculty member, I could go through the gates in both directions, unlike students.

Now I waited with the robot, looking around at the silent dormitories. Finally, three students approached from different directions, masked and holding cell phones. Each of them entered a code on a touch screen at the back of the robot, and a compartment popped open, revealing a package inside.

One of the students told me that she had ordered her package through Taobao, China’s largest e-commerce site, which is owned by the Alibaba Group. Before the epidemic, students retrieved their packages at a campus depot managed by Cainiao, another company mostly owned by Alibaba, but now the robot was also making deliveries. The student said that the machine had telephoned and texted her as it approached her dorm.

For the next half hour, I followed the robot, assuming that eventually it would lead me to its master. Whenever I biked too close, a horn sounded; if I swerved in front, the robot stopped. There was no response when I tried shouting at it. Periodically, the machine pulled over—“Daoda zhandian! ”—and masked students appeared, clutching phones and making a beeline in my direction. On the silent campus, it felt like a scene from a horror film: “Children of the Corona.”

At last, the robot parked in front of a Cainiao depot in a far corner of campus. A worker in a blue vest came out and started loading it with packages. “We have three of these now,” he said. He explained that Cainiao workers returned to off-campus houses every evening, so the robot was a way to reduce interactions with students.

I got back on my bike and headed to my office. Along the way, I passed a series of white tents marked with the words “China Health,” in English. In one, a masked nurse was seated behind a table with two glass thermometers in little boxes. She told me that, if somebody showed a high temperature at a checkpoint, that person was sent to a tent for a more careful reading. The next step, if necessary, was a campus clinic for a swab test. I continued to my office, where a package was waiting on my desk. It contained some tools that the university had provided for my return to the classroom: five surgical masks, a pair of rubber gloves, a box of Opula alcohol prep pads. Despite the three-month absence, everything looked fine in the office. Somebody or something had been watering my plants.

I had arrived at the university last August, to teach nonfiction writing and freshman composition, in English. My family and I moved to Chengdu, the capital of Sichuan Province, in part because it’s the region where I served as a college instructor in the Peace Corps, from 1996 to 1998. In those days, Sichuan was relatively poor, and most of my students came from the countryside. I hadn’t taught since then, an absence that essentially spanned a generation—twenty-one years.

I had returned to Chengdu in the hope of reconnecting with Chinese education, and I looked forward to meeting young people in the classroom. But, when the spring semester began, I found myself shuttered at home, in central Chengdu, trying to figure out how to use an online platform that had been hastily prepared by my department. Nearly thirty million college students were being educated online, along with an estimated hundred and eighty million Chinese schoolchildren. Beginning at about eight o’clock every morning, these users started logging in to platforms that were sometimes overwhelmed by the increased traffic of the online semester. Many elementary schools didn’t attempt interactive classes. My daughters, Ariel and Natasha, attended third grade at a local public school, and their teacher posted short video lessons that parents could stream whenever their connection made it possible.

The American-style Zoom course, with everybody appearing onscreen, wasn’t used by any of the teachers I knew in China. Our students were invisible: if a camera was turned on, it featured only the instructor, although even that could be problematic. Early in my nonfiction class, I tried to live-stream a lecture, but the system froze and crashed so many times that I gave up. After that, I avoided video. Every week, I prepared low-resolution photographs, maps, and documents to share onscreen, and my students and I communicated through audio and text.

In three classes, I taught about sixty students, only one of whom I had met in person. I frequently called on somebody, asking her to turn on her microphone, and slowly I began to connect voices with names. Chinese students often give themselves English names, and in the nineteen-nineties, when there was little contact with outsiders, my classroom had been full of Sino-Dickensian characters: a tall boy named Daisy, a pretty girl named Coconut. Twenty years later, I still have photographs of Lazy, who had freckles, and Yellow, who wore wire-rimmed glasses, and House, who was as skinny as a Sichuanese scarecrow. Back then, rural Chinese took pictures seriously—they stood in formal poses and rarely smiled.

Now I had no faces, and the names seemed to have entered a more traditional era. My freshman writing classes included Agnes, Florence, James, David, Andy, Charles, Steve, and Brian. Whenever these names popped up onscreen, I remembered kids I had grown up with in mid-Missouri—in 1980, I attended fifth grade with three Brians. When was the last time any American named his kid that? But nowadays the Chinese were making Brians in Chongqing. Most Sichuan University students came from the country’s new middle class, and I wondered about tracking China’s rise through English names—someday, perhaps, the decline would begin, with the Caitlyns, the Aidens, the Madisons.

I was glad to have a senior named Sisyphos in my nonfiction class. There were still some unusual names, although now they often reflected sophistication. In one freshman section, I had a sports fan called Curry and a rap aficionado named Rakim. Curry, who always wore blue and gold and fiddled with his mouth guard during online class (at least in my mind’s eye), wrote a sharp paper about the problems of China’s national soccer program. Rakim analyzed a reality show called “New Rap of China,” which, for some reason, had banned any Chinese contestant who wore dreadlocks. Despite being stranded in eastern Hunan, Rakim was aware of the appropriate capitalization for American ethnic groups. He wrote, “In my point of view, this rule is not only an insult to Black Culture, but also an offense to the rights that participants should have.”

Their voices came from all across the country. Through the years, institutions like Sichuan University have steadily become less regional, as part of a larger improvement in higher education. I often gave my students surveys, in order to get a sense of what their lives were like. They were scattered among more than fifteen provinces and municipalities, from Yunnan, in the far southwest, to Jilin, on the North Korean border. But all of us began the semester in effectively the same situation. During week one, I asked students about their circumstances, and more than a quarter responded that they hadn’t stepped outside their housing compounds in a month.

The Chinese lockdown was more intense than almost anywhere else in the world. Neighborhood committees, the most grassroots level of Communist Party organization, enforced the rules, and in many places they limited households to sending one individual outside every two or three days to buy necessities. If a family were suspected of exposure to the virus, it wasn’t unheard-of for their door to be sealed shut while tests and contact-tracing were being conducted. One student I had taught in the nineties sent a photograph of a door in her community that had been closed with two official stamps. “I haven’t seen such things since I was born, but people who are older must have some memory of such scenes,” she wrote, referring to the Maoist campaigns. “We are becoming numb, which may have more bad impact than the virus, in the long run.”

In my own household, I could see the negative effects on my daughters, who were desperate for interaction with other children. But it was also true that the strict Chinese shutdown, in combination with border closings and contact tracing, had eliminated the spread of the virus in most communities. February 20th, the day of my lockdown trip to campus, turned out to be the last day that the Chengdu authorities reported a symptomatic case from community spread. The city has a population of about sixteen million, but since late February there have been only seventy-one symptomatic cases, all of them imported. Virtually every case has involved a Chinese citizen who arrived on an international flight and proceeded directly from the airport to treatment and quarantine. Chengdu’s success was typical in China. In one of my surveys, I asked students if they personally knew anybody who had been infected. None of them did.

During week six, I asked, “Are you currently allowed to go outside in your community? Are there any restrictions on your movement?” Again, the responses were unanimous: from Yunnan to Jilin, my students were now mobile. I decided to send them out to do some reporting.

The only student I had met in person was named Serena. She lived in a fourth-tier city in northeastern Sichuan, where her parents worked modest jobs. Whenever I called on Serena in class, I heard traffic sounds: engines, horns, voices. Later in the semester, she explained that her building was poorly constructed, with thin walls, and there was a busy road outside. Serena was an only child, like almost all of her classmates, but she seemed to lack some of their confidence about the future. Once, I asked my students if they expected their lives to be better than their parents’ generation, and, out of fifty-two respondents, only Serena and two others thought that they would be the same or worse.

I had rejected Serena the first time she applied for my nonfiction class. When I was preparing to move to China, I had asked applicants to submit writing samples, in order to limit the number of students. On the first day of the fall term, Serena showed up anyway, and then she sent an e-mail asking if she could audit. I wasn’t accepting auditors, but something about the writing in her e-mail made me think again. I told Serena that she could take the course for credit.

From the beginning, she stood out. She wrote beautifully—she majored in English—and I was particularly impressed with her reporting. She was small, shy, and unassuming, but she seemed to understand that these qualities could put people at ease. In the fall, I asked students to develop research projects, and Serena embedded with a group of charismatic Sichuanese Catholics who organized retreats and prayed and wept with the power of God. For her next project, she hung out at a Chengdu gay bar. This transition wasn’t as abrupt as it appears, because Chengdu is known for both its Christian and its gay communities. In America, such a pairing would defy logic—San Francisco and Colorado Springs, together at last. But Chinese Christians and queers both represent fringe communities, and they’re more likely to flourish in a place like Chengdu, which is far from Beijing and has a reputation for tolerance.

Serena’s reporting was part of a trend that I had noticed in the fall; namely, that many students were good at it. Sichuan University is among China’s top thirty or so institutions, but few of my students majored in media studies. Even in that department, it is uncommon for undergraduates to do much field work, because Chinese journalism classes emphasize theory. Initially, I wasn’t sure if self-directed projects would be appropriate for my students, especially the freshmen, who had just completed the gaokao, the national college-entrance examination. Preparation for the exam has intensified in the past twenty years, in part because of all the one-child households, which tend to focus energy and resources on education. As a result, gaokao prep has become a brutal grind, and high-school students have few opportunities to develop creativity or independence.

But I quickly learned that, for all the gaokao’s flaws, it produced diligent researchers. The students had an extremely high tolerance for boredom, which is a lesser-known secret of effective journalism. When I explained the importance of details—numbers, signs, slogans, quotes, facial expressions—they collected data accordingly. My freshman composition classes consisted entirely of engineers, and there was no logical reason for them to be assigned journalism projects, but nobody complained. Even among these only children, there seemed to be little sense of entitlement. Near the end of the fall term, when Serena was neck-deep in Catholics and gay bars, I realized that I had failed to properly register her for the course. The administration informed me that it was too late: she couldn’t receive credit. Serena’s response to her nonfiction experience—first rejected, then denied credit—was to ask politely if she could finish out the term’s work and then do it over again in the spring, this time on the books. That was one tradition that hadn’t changed: in China, a student always respects her teacher, even if the teacher is a moron.

When we emerged from lockdown, I asked the students to write about a person or an organization that was dealing with the effects of the pandemic. Near Nanjing, Andy’s family knew somebody who ran a ventilator factory, so he visited the plant, where he learned that production had increased more than tenfold. In Liaoning, in the far northeast, Momo researched a state-owned tobacco company that had suffered a steep drop in sales. In the U.S., there were reports of increased tobacco use during lockdown. But Chinese smoking is often social—people light up at banquets and dinners, and they give cartons of cigarettes as gifts. An accountant told Momo that one of the company’s post-covid strategies—and, by any measure, a new vision of public health—was to give away masks and disinfectant to retailers who purchased cigarettes.

I liked these glimpses of life from all over. In Xi’an, Elaine visited a lesbian bar, where she noted that the owner kept some of the beer warm, because of the traditional Chinese belief that cold drinks are bad for women. Sisyphos profiled a pharmacist, who outlined how one could skirt government rules on mask price-gouging, although his sense of responsibility had prevented him from doing it himself. Hongyi shadowed a loan manager at a state-owned bank in Chengdu. A new program granted deferrals to borrowers who had been affected by the pandemic, and Hongyi reported that three hundred and seventy people called the manager to ask about the program. The bank approved deferrals for twenty-two. At another branch, every applicant was rejected.

This was a recurring theme—in economic terms, individuals seemed to be largely on their own. The Party had never allowed the protections of independent unions, and across China salaries were cut and workers were laid off. In April, the country recorded the first economic contraction since the end of the Cultural Revolution, in 1976. But stimulus policies remained modest: instead of offering American-style cash payments to many citizens, the Chinese government preferred to give entrepreneurs some space to figure out their own solutions. In Chengdu, city officials allowed venders to set up stalls on the streets. Such venders were common in the nineties, before campaigns were launched to make the city more orderly. Now the stalls reappeared all at once, and the evening crowds in my neighborhood reminded me of how Chengdu felt more than twenty years ago.

Many venders told me that they had been laid off from low-level jobs in factories and other businesses. But even people with stable work often found their salaries reduced. In May, when I flew to Hangzhou, an Air China flight attendant explained that she and her colleagues were paid according to flight hours, and that she now received the minimum—a quarter of her normal salary. For pilots, the reduction could be even more severe: one man who flew for Hainan Airlines told me that for two months he received less than ten per cent of his usual wage. I had many such conversations, but people usually said they were fine, because they had savings.

They also had low expectations with regard to stability. The Chinese middle class was still too new to feel complacent, which was one reason they put away so much cash. And they were accustomed to sudden shifts in policy or circumstance. In Hebei Province, a student named Cathy profiled an entrepreneur who owned a small business that originally distributed liquor. Chen, the entrepreneur, had seen his sales plummet after 2012, when the Party banned using public funds for banquets and other entertainment, as part of a nationwide anti-corruption campaign.

In response, Chen switched to a less corruptible substance: milk. He successfully redefined himself as a milk distributor, but then, when the coronavirus arrived, everything collapsed again. Chen embarked on two months of ten-hour days riding along with his delivery crews, talking to the owner of every store on his route. He developed a series of clever promotions that, by the beginning of May, had increased his sales to their highest level ever. “In fact, I’m very grateful to the epidemic,” he told Cathy. “If not for that, I probably never would have gone to the shops with the salesmen again.” Throughout everything, he hadn’t changed his company’s name—it still contained the word “liquor.” Cathy asked if this was a problem for a guy who distributes milk. “They don’t look at your name,” Chen said. “They look at the things you do.”

While officials seemed to have faith in the economic resourcefulness of citizens, the approach to public health was completely different. Very little was left to individual choice or responsibility. The lockdown had been strictly enforced, and any infected person was immediately removed from his or her household and isolated in a government clinic. By early April, all travellers who entered from abroad, regardless of nationality, had to undergo a strictly monitored two-week quarantine in a state-approved facility.

I occasionally saw the Chinese term for social distancing—anquan juli—on official notices, but I never heard anybody actually say the phrase. Certainly it wasn’t practiced in public. Once the lockdown ended, subways, buses, and trains quickly became crowded; during my trip to Hangzhou, I flew on an Airbus A321, and all of the hundred and eighty-five seats were occupied. When I interviewed people involved in business or diplomacy, we shook hands like it was 2019. Pedestrians still spat on the street. Mask-wearing remained mandatory indoors and on transport, but otherwise little had changed about human contact.

My daughters’ third-grade class consisted of fifty-five students, a number that, when school resumed, was reduced to fifty-four—one girl got stranded with her family on vacation in Cyprus. There was some attempt to separate desks, but, with so many people in a modest-sized classroom, any distancing was a game of inches. Students entered school through a tent tunnel equipped with a body-temperature scanner. A sign in the hallway listed lyrics to a new song:

Returning to school, what can we do?

Don’t be afraid, listen to me.

Wear a mask, study well.

It’s possible to protect both me and you.

Initially, the mask-wearing was enthusiastic. On the first day of music class, my daughters were shown how to play the recorder while masked—they lifted the bottom hem and shoved the instrument inside. During school pickup, I saw teachers who had rigged up masks with external microphones that connected to portable speakers on their hips. But, in the middle of May, the Chinese Ministry of Education declared that students no longer needed to cover their faces if they were in low-risk areas, and our school relaxed the rules. Some teachers stopped wearing masks, although nearly all of the children kept them on. They found a use for discarded masks during lunch: they turned them upside down, like little pouches, and filled them with bones and other food to be thrown away.

The school scheduled regular hand-washing breaks, and every afternoon an announcement sounded over the intercom: “Temperature-taking time has arrived!” Each day, my daughters had their temperature taken at least five times. This routine began at 6:30 a.m., when the class’s WeChat parent group engaged in something called Jielong, or “Connect the Dragon.” One parent would start the hashtag #Jielong, and list her child’s name, student number, temperature in Celsius, and the words “Body is healthy.” One by one, other parents jumped in—“36.5, Body is healthy”—lengthening the list with every dragon link. My account usually had about sixty of these messages every day. After eight o’clock, impatient notes were sent to stragglers: “To so-and-so’s father, please quickly connect the dragon!”

I lived in fear of the dragon. My mornings were a mess of fiddling with apps; one consisted of a daily form for the university on which I listed my temperature, location, and whether I had had contact with anyone from Hubei, the province that contains Wuhan, in the past fourteen days. If I missed the noon deadline, an overworked administrator sent a gently passive-aggressive reminder. (April 11, 12:11 p.m.: “Hi Teacher Hessler, How are you doing today?”) In addition, a QR code with a health report had to be scanned every morning for each of my daughters. I often felt overwhelmed, not to mention a little odd: during the first month of dragon-connecting, I received 1,146 WeChat messages listing the body temperatures of third graders.

I wondered how much of this was theatre. Epidemiologists told me that temperature checks, though useful, represent a crude tool, and they generally believe that social distancing is more effective than mask use. One epidemiologist in Shanghai told me that people should wear face coverings, but he noted that there are no data on the level of effectiveness as public policy, because mask use could also affect behavior. And, while Chinese officials required citizens to wear masks from the beginning of the lockdown, they didn’t actually depend much on them. China never allowed residents to move freely in a community with significant viral spread, hoping that masks, social distancing, and good judgment would reduce infections.

Instead, the strategy was to enforce a lockdown until the virus was eliminated. The elementary school never bothered with more effective but disruptive policies—reducing class size, remodelling facilities, instituting outdoor learning—because the virus was not spreading in Chengdu. And, while the government hadn’t trusted people to set the terms of their own behavior during lockdown, it did depend heavily on their willingness to work hard for various organizations that fought the pandemic.

A number of my students, including Serena, researched neighborhood committees in their home towns. Serena took her usual dogged approach—for much of two months, she spent two or three days a week with a local committee. She told me that, before the pandemic, she hadn’t even been aware that these organizations existed. They were like ancient organisms gone dormant: back in the eighties and nineties, when the Party interfered more in private lives, neighborhood committees had been prominent. But there had been a long period during which they played a diminished role for most residents.

After President Xi Jinping came to power, in 2012, he set about strengthening Party structures, including a new emphasis on neighborhood committees. This process was accelerated by the pandemic, and Serena and other students observed how quickly these organizations grew in their communities. With new government funding, committees hired contract workers, some of whom were local shop owners who had been forced to close down. Neighborhood crews went door to door, giving out information, questioning residents to see if they had been to high-risk areas, and helping with contact tracing. Sometimes they made mistakes. At the end of January, an official whom Serena profiled was assigned to a compound with 1,136 units. For two days, the official and some subcontractors worked from eight in the morning until midnight, climbing stairways and knocking on doors. But they missed one apartment: when there was no answer, they failed to leave a note, and they didn’t go back for a second check.

Soon that kind of error was no longer made. In the time that Serena spent with the committee members, she observed them becoming more professional. They came to understand their role, along with the stakes of the pandemic. The Chinese state press reported that fifty-three members of neighborhood committees died while working to control the virus. Others were fired or chastised for even the smallest mistakes. That’s what happened to the official in Serena’s home town who missed the apartment—he was forced to write a self-criticism, another long-standing Party tradition. It turned out that the apartment contained the only coronavirus case in the residential district, he told Serena. The occupant—I’ll call him Liu—had been taking a shower when the committee members knocked.

At a party a week earlier, Liu had had a long conversation with a d.j., who, it was later learned, had been infected by someone from Hubei. Liu was thirty-five, single, and highly energetic. The details of his post-contact movements are listed on a public WeChat account maintained by the city government. In China, such case histories are often available, as resources for local residents. Liu’s case history notes that, during the first three days after he is unknowingly infected, he visits a bar, a store, two pharmacies, three gas stations, and six restaurants. Liu’s tastes are eclectic, ranging from a pancake restaurant to a frog-and-fish-head restaurant. He picks up a friend named Huang, and he visits his elderly parents. He goes to work. He gets a fever. Post-fever, Liu hops over to a few more pharmacies, and then he keeps going: he picks up a friend named Li; he visits his parents again; he goes to another party. On the WeChat account, Liu is the Liupold Bloom of northeastern Sichuan, with every step of his urban odyssey recorded in terrifying detail. When is this guy going to stop?

Such meticulous case histories were prepared by contact tracers who worked under the direction of the Chinese Center for Disease Control. There are about three thousand C.D.C. branches in China, each branch containing roughly a hundred to a hundred and fifty staff members. Despite these numbers, the Chinese C.D.C. has traditionally been underfunded, like Chinese public health in general.

Approximately ten thousand contact tracers worked in Wuhan, where more than eighty per cent of China’s deaths occurred. Epidemiologists told me that the tracers were divided into teams of between five and seven, with each group directed by an individual who had formal training in public health. Other team members might have no health background, but they came out of the same detail-oriented national educational system that had produced my students, and they often had local knowledge. Many tracers worked for neighborhood committees or other government organizations, including the police. As the virus spread, tracing teams were established across the country, and the C.D.C. recruited others who had technical expertise.

In Shanghai, a twenty-four-year-old named Jiang Xilin was contracted to work on various projects for the C.D.C. and the Gates Foundation. Jiang is in his third year of a doctoral program at the University of Oxford, where he studies genomic medicine and statistics. He had won a Rhodes scholarship to Oxford after studying at Fudan University, in Shanghai. In early March, Jiang worried about the initially complacent British response to the coronavirus, and he asked his advisers for permission to return to China and study remotely. “They all thought I was crazy to want to go back at that time,” he told me.

In Shanghai, Jiang helped the C.D.C. with modelling, computer programming, and writing proposals. “The first weekend, I got a call at 12 a.m. on a Sunday evening,” he told me. “Nobody said, ‘I’m sorry to disturb you so late.’ They said, ‘Did you get that proposal done?’ I said, ‘No,’ and they said, ‘We need that report by noon.’ ” He quickly became accustomed to such demands. Jiang also learned that, if a late-night call went silent, it often meant that the person on the other end had fallen asleep from exhaustion.

By then, many overseas students and others were coming home. It would have been useful to know exactly where they had been, so Jiang wrote a proposal requesting that Tencent, the company that owns WeChat, provide the I.P. log-in information for returnees. “They rejected me because of the data privacy,” he said. He was told that Tencent was adamantly opposed to its data’s being used in this fashion.

Once, when Jiang and I met for dinner in Shanghai, he showed me how our phones automatically sensed each other via Bluetooth. Such data could be used to figure out who had been in close proximity to an infected person. In another C.D.C. work meeting, a colleague of Jiang’s suggested using this tool. But her idea was quickly dismissed. “They said, ‘This is a violation of data protection. We can’t do that,’ ” Jiang explained. “It was surprising to me.”

It surprised me, too—given the heavy-handed tactics of many lockdown policies, I had assumed that the government used any tools available. But there seemed to have been some resistance from prominent tech companies. Tencent and Alibaba helped the government develop “health code” apps that assist in monitoring and controlling the virus’s spread among citizens, but these tools are much less sophisticated than programs used in South Korea and Singapore. In Europe, virus-alert apps based on software developed by Google and Apple have been downloaded by millions of users, and the apps rely on Bluetooth signals to detect close contact with infected individuals.

In some parts of China, the health-code apps register a change in a user’s location largely through a manual data transfer: if the user checks in with his I.D. at an airport, for example, or if his license plate is recorded at a toll booth. An epidemiologist in Shanghai told me that one Chinese city with a flourishing tech industry had commissioned the development of a much better tool that combines G.P.S. data and artificial intelligence to alert anyone who comes into the proximity of an infected person. “But that system was never implemented, even in that city,” the epidemiologist, who asked not to be identified, said. “It could not get approval from somewhere in the government system because of data privacy.” He noted that while some of the apps track location through cell-phone towers, they don’t use the more accurate G.P.S. data.

“One can argue that what was most useful for covid was old science,” he continued. “The methodology is from fifty or seventy years ago. It has not changed.” Jiang Xilin told me that, when the proposals to use automated data collection were rejected, the other C.D.C. researchers grumbled. But then they buckled down and continued to do the hard legwork of phone calls and face-to-face interviews. The C.D.C. policy is that, whenever a new case appears, contact tracers are called immediately, even in the middle of the night. They are given eight hours to complete the tracing.

In June, after Beijing had reported no locally transmitted cases for fifty-six days, there was a sudden outbreak at a wholesale produce market called Xinfadi. The epidemiologist in Shanghai told me that the place was well managed: masks were required, and anybody who entered had to show his health code and have his temperature taken. Even so, more than three hundred people were infected, and all the warning systems had failed to catch it in the early stages. The first alert came when a man in his fifties felt sick and went to a hospital to request a test. It was another example of old science: effective public communication. The man not only recognized his symptoms but travelled to the hospital by bicycle, as officially recommended, in order to avoid infecting others on public transport. Afterward, the government locked down parts of Beijing, and, within a month, nearly twelve million residents were given swab tests. The city had the capacity to test four hundred thousand people per day.

“Recent outbreaks in places that had not recorded confirmed cases for weeks show that the virus is very difficult to completely eliminate,” Gabriel Leung, the dean of medicine at the University of Hong Kong, told me. “Coronaviruses tend to cluster in super-spreading events. It can have an explosive outbreak out of the blue.”

It can also do nothing. The Liupold Bloom of northeastern Sichuan, whose unchecked voyage across his city lasted for eight days, appears to have infected a grand total of zero people. In a sense, the outcome made no difference: one neighborhood-committee member in Liu’s city was punished, just as the outbreak in Beijing resulted in six officials being disciplined. Liu himself was never very sick. He spent a week isolated in a coronavirus ward, felt fine, and tested negative. Then, after nearly two more weeks of strict quarantine in a hotel, he tested positive again and returned to hospital confinement. By the time Liu was finally released to the world of pharmacies, gas stations, and frog-and-fish-head restaurants, he had spent sixty-five days in medical isolation. Serena asked for an interview by phone, but a neighborhood-committee member said that the experience had left Liu too psychologically fragile.

During week nine, in late April, I reviewed some student writing with a freshman class. At the end of the session, I asked if there were any questions about the essays. After a long pause, a student typed into the text box, “Can you talk about what is happening in the U.S.?”

Throughout the term, tension between America and China had shadowed our interactions. In week three, a Chinese official claimed on Twitter that the U.S. Army might have brought the virus to Wuhan; in week four, Donald Trump started referring to “the China Virus.” After American fatalities exceeded China’s, during week six, the U.S. numbers exploded: ten times as many deaths as China by week ten, twenty times by week fifteen. During week sixteen, my nonfiction class discussed a book excerpt by Ian Johnson, a Beijing-based writer for the Times, and I told them that Johnson’s visa had been revoked back in week four. It was part of a tit-for-tat exchange between the two governments, which took turns expelling each other’s journalists.

Later in the term, some student essays referred to the death of Freud, which initially confused me. Then I realized that this was what happened when a student read Chinese news reports about George Floyd—Fuluoyide—and ran the name through a machine translator back into English. Even with all the improvements in technology, distance still mattered, and I longed for face-to-face interactions during such a time. I did my best to talk about what was happening across the Pacific, but students were cautious about giving their own opinions via audio and text. I remembered how much I had depended on visual clues in the nineties, when certain subjects could make a classroom of Chinese students drop their heads in discomfort: the Cultural Revolution, or Chinese xenophobia, or any reference to the country’s poverty.

Nowadays, in a much more prosperous Chengdu, people were less sensitive and less restrained when talking in person. They laughed about Trump—in many people’s eyes, he wasn’t to be taken seriously. As the spring wore on, conversations often included a standard conclusion: the pandemic showed that Chinese value life over freedom, whereas Americans take the opposite approach. I disliked such simplifications, which failed to consider the initial Chinese coverup of the virus, or the government’s policies in Xinjiang and Hong Kong, or the fact that any number of democracies were handling the crisis much better than the Americans. (Also, the U.S. doesn’t have state-owned tobacco firms that engage in mask ’n’ Marlboro promotions.) I tried to convey the idea that the current American failure doesn’t narrowly reflect national character or values but, rather, a collapse of system: a crisis of leadership and institutional structures.

And many aspects of the Chinese strategy could never be adopted in America or in any other democracy. The strict policy of isolating individuals who test positive is also applied to children, who are separated from their parents even if they are asymptomatic. In June, a year-old Pakistani arrived on a flight and tested positive. For more than a month, the baby was held for medical observation.

Such dramatic examples tend to distract from more useful elements of the Chinese approach. The Chinese epidemiologist in Shanghai had also worked for many years in the U.S., and I asked if there was anything that Americans could realistically learn from China. “Community engagement,” he said immediately. “We don’t have the neighborhood-committee structure in the U.S., but it’s important to find some alternative.” He noted that public-health services might have served this purpose if the American system had been properly funded. Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Center for Health Security, told me that contact tracing is something of a lost art in the U.S. “We did a study of the measles outbreak in 2019, and they were doing minimal contact tracing,” she said. “It’s so incredibly resource-oriented, and public health has been decimated.”

From my perspective, there are also issues of education and effort. Despite the political indoctrination involved in Chinese schooling, the system teaches people to respect science. Hard work is another core value, and somehow society has become more prosperous without losing its edge. Nearly a quarter century ago, I taught young people who were driven by the desire to escape poverty; these days, my middle-class students seem to work at least as hard, because of the extreme competitiveness of their environment. Such qualities are perfect for fighting the pandemic, at least when channelled effectively by government structures. In comparison, the American response often appears passive—even enlightened citizens seem to believe that obeying lockdown orders and wearing masks in public is enough. But any attempt to control the virus requires active, organized effort, and there needs to be strong institutional direction.

Instead, the flailing American leadership seems more interested in finding scapegoats, sometimes with a racial tinge—the Kung Flu and the China Virus. Throughout the spring, the Chinese government periodically responded by lashing out at the U.S. and other foreign countries, but such tensions had little impact on my life in Chengdu. Daily interactions remained friendly, and people often made a point of telling me that the problems between governments had nothing to do with our personal relationships.

But I worried about my daughters, who were the only Westerners at a school of some two thousand students. Our isolation increased throughout the spring: most of my American acquaintances had left, and it became rare to see a non-Chinese person on the street. At the end of May, the twins told my wife, Leslie, and me that a boy in their class had made some anti-American comments, but we didn’t say anything to the teacher. Virtually all of the girls’ classmates treated them warmly, and, with everything on the news, it seemed inevitable that there would be scattered instances of anti-American sentiment. That week, George Floyd had been killed, and the American death toll from the coronavirus was approaching a hundred thousand.

The teacher, though, responded quickly. The following Monday, she stood before the class and told a story that, in the Chinese way, emphasized science, education, and effort. She talked about Elon Musk, and she described how his California-based company had successfully launched a manned rocket into space the previous weekend. At the end of the story, she said, “Every country has its strong points and its weak points.”

During week sixteen, I finally entered the classroom. For more than a month, there had been rumors that undergraduates would return, as they had in some other provinces. But the final decision was always left to local officials, because, in the Chinese system, they are the ones who would be punished in the event of an outbreak. At Sichuan University, administrators seemed to decide that it wasn’t worth the risk. Senior students were called back to take their final exams, along with others who had made special requests, but most younger undergraduates were encouraged to stay home. I was disappointed—I had hoped to finally meet everybody. None of my first-year students made it back to campus.

In the end, it became another type of theatre: a dress rehearsal. The university introduced the fever tents, the delivery robots, and the facial-recognition scanners, but I sensed that administrators were mostly testing systems in preparation for the fall. Chinese epidemiologists told me that they were concerned about the possibility of a second wave of infections. Despite the country’s current success, they never seemed satisfied. “There’s no long-term plan,” a professor of epidemiology in Shanghai said bluntly. “No country has a long-term plan.” Another epidemiologist expressed concern about the lack of social distancing, believing that China needed to be prepared to use measures that were less aggressive than a lockdown but more effective than mask-wearing. “This is something we need to fix,” he told me. “There are smart people in the Chinese C.D.C. who realize this.”

The first week back, only four students showed up to my nonfiction class: Serena, Emmy, Fenton, and Sisyphos. It was like having a studio audience—the five of us talked back and forth, but we used headphones and microphones to connect with the others, who were still scattered across the country. Each returnee had a reason for coming back. Emmy was the only student who came from the countryside, and, like Serena, she had grown tired of being in a home that was loud and crowded. Fenton needed to get some dental work done at a university hospital. And Sisyphos, as a senior, was required to return for exams.

He arrived wearing a mask, but he took it off when he saw that the others were uncovered. He was tall, with slightly wavy hair, and he said that in the fall he would enter a graduate program in economics, in Shanghai. It seemed that most seniors were going to grad school; the government had expanded academic programs in order to reduce pressure on the job market.

Even online, I had sensed that Sisyphos was shy, and I never put him on the spot by asking about his name. But now I did, and he reddened slightly. He explained that he had chosen it in high school, because he liked the Greek myth.

“So where’s the rock right now?” I asked. “Is it high or low?”

Sisyphos brought his hand level with his chest. “It’s in the middle,” he said.

I often wondered what the spring’s experience would mean to this younger generation: the Children of the Corona. “This is the first time that I feel so close to history, and I was actually reporting on it,” Serena wrote, in one of her last assignments. “I guess I’ll start to keep notes from now on.” She said that spending time with the neighborhood committee, where she saw officials and police fighting the pandemic, had also made her think about the previous term’s research. She realized that in the past such devoted and hardworking neighborhood officials had been turned against groups like the Catholics and the gay community. “All of them are good people,” she wrote. “They just happen to be in different places, and sometimes in conflicting situations.”

Throughout the semester, I had tried to connect with the voices in my headphones, and I knew that such exchanges would become even harder in the future. A number of students had abandoned plans to study abroad or to attend graduate school in America. In July, after the Trump Administration ordered the closure of the Chinese consulate in Houston, the Chinese responded by shutting down the U.S. consulate in Chengdu. Some of the damage in U.S.-China relations was bound to be long-lasting, and, in any case, the national experiences had diverged. By the time I handed in final grades, in early July, the U.S. was recording more cases every two days than the Chinese had reported during the entire pandemic.

And the lessons that a young Chinese drew from the crisis were likely very different from those of a young American. In my students’ last essays, many expressed a renewed faith in their government. Jiang Xilin, the Rhodes scholar who had fled Oxford for Shanghai, told me that he had also noticed a change in his peers from the élite Fudan University. “Even my most anti-government friends began to have trust in the government,” he said. For my last survey, I asked the students to rate their feelings about the future on a scale of one to ten, with one being the most pessimistic. After everything that had happened—the collapse of U.S.-China relations, the explosion of the pandemic, the death of half a million people worldwide—the average rating was 7.1.

Only three students came to the final nonfiction session, in week seventeen. Sisyphos was gone: like all seniors, he had finished early. Somehow, Serena, Emmy, and Fenton had learned that my birthday was the previous day, and they threw a surprise party. The robot had brought them balloons, confetti, and letters for a birthday sign, and they had a cake and a spicy Sichuanese dish called maocai delivered to one of the gates. Serena printed and bound a book with messages and photographs from her long-distance classmates. In the Chinese way, the notes were self-deprecating. “Thank you for reading my rough essay (quite a torment to you),” one student wrote.

For four months, I had known them by their voices, their writing, and their projects. Now, in the pages of the book, I finally saw faces: Cathy, who researched the liquor-milk man in Hebei; Elaine, who spent time at the lesbian bar in Xi’an; Hongyi, who shadowed the Chengdu bank manager. The details mattered, as we had emphasized all semester: Patrick wore glasses, and Dawn had shoulder-length hair, and Meredith stood on a beach with a dog. All of the students were smiling, their poses natural, unlike the photos of old. I wished we had met in person, but it was good to know they were out there somewhere.