You entirely missed my point which was that a good portion of the so-called 25,000 won't want to leave, because they are dualies who will want to stay in Lebanon.
Your point is a good one if there are those who have means and resources that want to stay. But I don't see how one can discriminate against people holding an American passport.
Of course there are going to be some special names to get out first. In fact some have already although it's less than a hundred.