What might an urban doom loop look like? Here is one brief description:

The worst-case scenario would go like this: With more people working from home, companies from Milwaukee to Memphis are rethinking their leases or pulling out of them altogether. That drives vacancy rates up and makes it harder for landlords to attract new tenants or sell buildings for a healthy price.

Then property owners might struggle to pay off their mortgages or clear other debt. Business districts would dry up, stifling tax revenue from commercial properties or employee wages. Shoppers and tourists would have fewer reasons to venture downtown to eat or shop, choking off spending and forcing layoffs at restaurants and retail stores.

“Once those offices are empty, there are few alternatives and not a lot of life after hours,” said Stijn Van Nieuwerburgh, a professor of real estate and finance at Columbia University’s Graduate School of Business who is one of the authors of a paper that coined the “urban doom loop” phrase. Midsize cities “have a much bigger chasm to cross than what New York City has to go through. The situation is worse in those places with so little else in place.” He added, “It is a train wreck in slow motion.”

Once the primary use of a district starts disappearing, it can be hard to reverse the pattern. This is true in downtowns where much of the space is used for offices. It can be true for other uses as well, such as when retail dries up at shopping malls or a particular industrial activity slows down in a one industry place.

Is the primary way of addressing this right now simply to hope it the doom loop does not get too far? Are there any interventions that could help protect against worsening conditions? This could be an interesting time for experimentation across American cities as places and firms adjust to less need for permanent office space.