I mean, you're both kind of right. I'm no doctor but it seems like something doctors (good doctors, anyway) would seriously consider in regards to this. On the one hand, they're leaving people to the wolves. On the other, there is nothing you can do in the US if it gets that far that will outweigh the good you can do elsewhere. But then, is that actually true? This isn't the literal same as WWII, it's just extremely similar, a pattern we are able to recognize this time around because it happened before and was well-documented. It's possible that this time, leaving would in fact cause more harm than good. But if you have a family... Well, I can't blame you for protecting your own kids over your patients and their kids, as long as you don't throw someone else under the bus.
It's complicated. When there's that many variables, all you can do is trust your gut. No one can predict the future that well, if at all.