One of my more reasonable liberal acquaintances pointed out that it might open the door to foreign victims of U.S. military activity suing the U.S. in the same manner. Does he have a point, or is it apples and oranges?
I think so. But that should not prevent the 9/11 victims from seeking justice, IMO. Justice should be blind, as the old saying goes. As for any future cases, let the chips fall where they may.
As a side note, remember how Obama bowed to the Saudi king? I suspect that Obama will veto this bill not because of your friend's point, but because a lawsuit would expose the Saudi's deep involvement in 9/11.