The most important thing to understand about China’s social credit system is that it is popular. A 2018 poll by the Free University of Berlin found that 80 percent of respondents had a favorable view of the social credit system, with wealthier and more educated users the most in favor.

It’s easy to imagine a vaccine passport system in the United States morphing into something similar to the Chinese model—and being equally popular among the wealthy and educated—especially if at first it was confined to coronavirus-specific measures. Get caught taking your mask off indoors? That’s a two-week hold on your restaurant privileges. Your church had more than the permitted number of unmasked singers? That church is restricted to video streaming services for the next three months.

There are plenty of people who would consider such measures dystopian but who have no problem with a bare-bones vaccine passport. What those people have to understand is this: Once Americans get used to scanning a QR code every time they go into a building, there is no way to arrest that trajectory at the specific point you prefer. We have seen how easily decision-makers are captured by the most deranged Covid hawks. The same forces that just led to an outdoor mask mandate in Oregon, in the face of all scientific evidence, will be brought to bear on any vaccine passport. It will be a never-ending ratchet.