Today we’ll explain why the CDC now wants vaccinated people to wear masks indoors again. Just a few months ago, the CDC said vaccinated people didn’t have to wear masks in most settings. But this week the agency reversed course, saying vaccinated people should wear masks at times. Vaccinations have stalled, and some unvaccinated people still refuse to wear masks. A lot of Republican congresspeople and governors railed against mask wearing and refused to wear masks themselves.