Every soldier thinks something of the moral aspects of what he is doing. But all war is immoral and if you let that bother you, you're not a good soldier.
I try to do that in this book without preaching - to try to do as you just said that you really have to defend the First Amendment rights of everybody.
Mostly this problem is contained in the fact that the US makes it so difficult for Canadians to get green cards (you heard it here), but if an American orchestra really wants a player, they have their ways.