We need to talk about South Korea.Through 2020 and 2021, South Korea chased zero Covid with strict border controls, aggressive testing and tracing, and a vaccination campaign that reached nearly its entire adult population with mRNA (and some DNA) shots.The country didn’t quite get to zero. Infections and deaths rose slowly last year. But it came close enough that the usual highly credentialed public health experts held it up as a light among the nations. […]On Thursday, South Korea reported 600,000 new Covid infections - the equivalent of more than 4 million in the United States. In a single day.Covid...