The alternative to mass surveillance is mass testing. Romer’s proposal is to deploy testing on a scale no one else is contemplating — 22 million tests per day — so that the entire country is being tested every 14 days, and anyone who tests positive can be quickly quarantined. He shows, in a series of useful simulations, that even if the test has a high false-negative rate, the retesting is sufficient to keep the virus contained, and thus the country can return to normalcy rapidly. Of the various plans, this one seems likeliest to permit a true and rapid economic recovery.

But it is hard to imagine a testing effort of this scale, too. So far, America is struggling to get into the millions of tests per week. This plan requires tens of millions per day. Most experts I’ve spoken to doubt that’s realistic anytime soon, though some believe it’s possible, eventually. So far, we’ve added testing capacity largely by repurposing existing labs and platforms. To add more, we need to build more labs, more machines, more tests. And there are already shortages of reagents, swabs, and health workers.

But even if those constraints could be overcome, how are these 22 million daily tests going to be administered? By whom? How do we enforce compliance? If you refuse to get tested, are you fined? Jailed? Cut off from government benefits? Would the Supreme Court consider a proposal like this constitutional?