Also it seems incredibly unfair to the majority of foreign students in the US who will never have anything to do with terrorism. A lot of my friends are here on student visas, so I may be taking this a little personally, but it just seems like a really stupid thing to do, not to mention being bad for international relations and probably working to reduce the number of foreign students who come to the US (a bad thing, in my mind, which will only serve to enhance the isolationist image of the US and further our alienation from the rest of the world).
Isn't this basically the punishing of the moral for the crimes of the immoral in much the same way conservatives are always saying that taxes are punishing the successful for the good of the unsuccessful?