This is not to minimize the indiscriminate and widespread damage that the disease has caused by disrupting the global supply chain. With shortages of everything from auto parts to generic medicines and production delays in things like iPhones and Diet Coke, a great deal of pain is coming from the closing of Chinese factories. That proliferating damage has central banks and financial analysts talking about a global recession in the coming months.

Nor is it to discount the possibility that the United States will be spared the worst effects. Scientific and public health efforts might limit the spread of the virus or quickly find a treatment or vaccine. The warmer weather of summer might slow the spread of the coronavirus as it usually does with the seasonal flu. Many things could prevent an outbreak as large as the one in China.

But it is to say that an equivalent outbreak in the United States might easily have a worse economic impact.

As a baseline, several factors work against the United States. China’s authoritarian government can quarantine entire cities or order people off the streets in a way that would be hard to imagine in America, presumably giving China an advantage in slowing the spread of the disease. In addition, a large share of American workers lack paid sick days and millions lack health care coverage, so people may be less likely to stay home or to get proper medical care. And 41 percent of China’s population lives outside urban areas, more than twice the share in the United States. Diseases generally spread faster in urban areas.

Beyond those issues, however, is a fundamental difference in economic structure: When people pull back from interacting with others because of their fear of disease, the things they stop doing will frequently affect much bigger industries in the United States.