Why are we not restricting travel to and from New York State?

So we put a travel ban in place on China, South Korea, Iran and Europe at a time when none of these areas was reporting the sort of numbers that the State of New York is reporting now. Yet both airports are open and New Yorkers are being allowed to fly around to the rest of the country?

If a travel ban made sense for countries that were hot spots for the virus, then it certainly should make sense within our own borders. I know there are legal issues with the Federal Government picking and choosing whether or not a state can be locked down (the constitution seems to side with the idea that these decisions are up to the States). But I see no reason why the President could not order a Federal shut down of air travel. At least any travel that takes people out of New York on non-essential travel.

Perhaps there is some numbers out there that suggests that the air travel is limited in New York to almost nothing. But as a matter of optics, it would be nice to have something official put in place.