"The South Korean government has been among the most ambitious when it comes to providing the public with free and easy testing options. It has the ability run about 15,000 diagnostic test per day and has conducted 196,000 tests to date nationwide, free of charge. Authorities in the city of Goyang even set up drive-thru testing booths.
"Detecting patients at an early stage is very important and we learned the simple lessons by dealing with this virus that this is very contagious -- and once it starts, it spreads very quickly and in very wide areas," Park said. "Raising the testing capability is very important because that way, you can detect someone who's carrying the virus, then you can contain the virus.""
http://edition.cnn.com/2020/03/09/asia/south-korea-coronavirus-intl-hnk/index.html
So exactly what the US is not doing.