The vaccine resisters offer all kinds of reasons for refusing the free shots and for ignoring efforts to nudge them to get inoculated. Campaigns urging Americans to get vaccinated for their health, for their grandparents, for their neighbors, or to get free doughnuts or a free joint haven’t done the trick. States have even held lotteries with a chance to win millions or a college scholarship. And yet there are still huge numbers of unvaccinated people. Federal, state and municipal governments as well as private businesses continue to largely avoid mandates for their employees out of fears they will provoke...