If you are going to act within the constitution, the Feds can't override a governor just because they are being a jerk.
Or at least not simply. With Bush, with the mythology about him from the left, it would be a damned if you do, damned if you don't situation.
I don't know how he could do it without provoking a constitutional crisis.
Okay. But would it really be un-Constitutional to do a mercy air drop of water for thousands of people dying in the street?