The argument is straightforward and seemingly incontestable: The coronavirus thrives among close clusters of human beings, and nowhere are humans clustered closer than in big cities. The virus’s toll seems to make the connection plain. New York City, the most populous and most dense urban area in the United States, was also the first to be devastated by the virus.

The pandemic will pass, but many fear that our response to Covid-19 may have ravaged urban economies for good. Lockdowns shuttered bars and turned restaurants into “ghost kitchens” whose primary patrons are overworked DoorDashers. The overnight shift to remote work obviated the need for office buildings and the vast economy that supports their workers, from public transit to corner stores. Online commerce, which had been decimating physical retailers for more than a decade, accelerated its crushing inevitability. Even cultural institutions seem at risk: If “Hamilton” didn’t lose much in the translation from the Richard Rodgers Theater to Disney+, perhaps the end is nigh for Broadway, too. Now that technology can shower us with many of the benefits of urban life while we laze about in giant exurban McMansions, why would we ever return to living and working so close together?

Here’s one answer: because neither the United States nor the world can do without cities. They are indispensable as engines of economic growth, catalysts of technological and cultural innovation — and they are one of the most environmentally sustainable ways we know of for housing lots of people.

Not only are cities worth saving, they are also ripe for rebirth. The virus presents an opportunity to remake urban life for the better, particularly by addressing its inequities.

Already, the pandemic has prompted cities around the world to embrace once radical-seeming ideas. In car-free streets and permanent alfresco dining, a picture of a more liveable city is emerging. But we can do a lot more than pedestrianise roads. In 2021 and beyond, we should make rebuilding our urban landscape a top priority.

Contrary to conventional wisdom, urban population density does not seem to have been the primary factor in the virus’s spread — note how Asian mega-cities like Hong Kong and Seoul combated the virus successfully, while many American rural areas suffered major outbreaks.

But in New York and other American cities, overcrowding within residences, caused by a lack of affordable housing, did exacerbate the contagion. So let’s fix that: In addition to loosening our antiquated zoning rules, perhaps vacant office buildings and retail space can be turned into apartments, lowering the cost of housing.

This is also our chance to remake crumbling urban infrastructure — to create more engaging outdoor public spaces and to radically improve public transportation.

Then there is climate change. Think of the coronavirus as a trailer for the horror flick of natural disasters to come. We have a chance to fortify urban space against future outbreaks of disease as well as the coming calamities caused by the changing weather — we can even do both at the same time. For instance, reducing automobile traffic in cities will not just cut emissions that warm the climate. It will also clean up the toxic air that hangs over our most populous areas, and is thought to increase the risks of respiratory diseases, including susceptibility to Covid-19. More walkable and bikeable urban design is good for the environment and our health; a study of commuters in Britain showed that biking to work was associated with lower risk of cardiovascular disease and cancer.

What’s important here aren’t the specific ideas, but the larger push for civic revitalisation. The coronavirus does not have to kill cities — just our old idea of what cities were, how they worked, and who they were for. Rethinking urban space in the aftermath of disease is hardly a new idea. If cities were going to be crushed by pestilence, they would have died millenniums ago. Disease has shaped the modern city, and the modern city has shaped disease.

The practice of epidemiology was born in the city, when John Snow, a London anaesthesiologist, tracked the spread of cholera to a contaminated water pump in 1854. And much of the civic infrastructure we now take for granted — public parks, garbage trucks, sewers — was put in place partly to curb disease. Cities have overcome disease before, and they can do so again.

Yet at the moment, a grand project to rebuild American cities feels terribly elusive.

Despite their economic and cultural importance, cities in the United States are often marginalised in politics and, more deeply, in our picture of how America should work.

About 80 percent of Americans live in urban areas, but most say they’d rather live somewhere else.

Republicans use cities as a cudgel — supposedly crime-ridden “Democrat cities” became a mantra for President Trump. Democrats depend on big cities and their surrounding suburbs for the bulk of their voters, but when was the last time you heard a national Democratic politician make a forceful case for the beauty, creativity and importance of cities — for all that we owe to them, and all we may yet gain from them?

If we are to rebuild American cities after Covid-19, we must recognise their value and sing their praises. We must learn to love their bigness, their inherent chaos, and admit how bereft we would be without them.

“Cities were once the most helpless and devastated victims of disease, but they became great disease conquerors,” wrote Jane Jacobs, the great urbanist, in “The Death And Life of Great American Cities.” Then she itemised their contributions: “All the apparatus of surgery, hygiene, microbiology, chemistry, telecommunications, public health measures, teaching and research hospitals, ambulances and the like, which people not only in cities but also outside them depend upon for the unending war against premature mortality, are fundamentally products of big cities and would be inconceivable without big cities.” Cities created the future. Now we must secure theirs.