Understanding the GOP Battle Over Vaccine Passports

Months into a mammoth health-messaging campaign encouraging Americans to get vaccinated against COVID-19, we can say two things with confidence about the cohort of people still playing hard to get. The first is that, in absolute terms, this group has shrunk and may still be shrinking. Gallup reported yesterday that fully three quarters of U.S. adults say they are already vaccinated or plan to be; last December, only 65 percent said they planned to get the shot.

The second, however, is that some subset of that cohort is looking less...