(1) WE DON’T KNOW FOR SURE, BUT PROBABLY MORE THAN WE THINK; (2) WE DON’T KNOW FOR SURE, BUT PROBABLY WORSE THAN WE THINK. Coronavirus in the US: how many people have it and how serious is the risk? My own opinion is that we should have stopped flights from China days ago. I understand why we haven’t — the economic impact would be huge, and the evidence is unclear — but I think we’re going to wind up wishing we had done it anyway. I hope I’m wrong, and I may very well be, but that’s my take.