Obisidan Wings http://obsidianwings.blogs.com/points out the real danger of Bushism:
But this administration does not recognize the existence of any such lines. They do not "have to" withdraw just because none of their plans have worked, the army is breaking, and the war has next to no popular support. They would "have to" withdraw only if someone put a gun to their collective heads and forced them to. They do not "have to" obey the law or the Constitution: they will only if they are literally compelled to. Likewise, they do not "have to" respect even the most basic principles of decency and humanity, even when obligated to do so by US law and treaties we have signed, which are, according to the Constitution, the law of the land. Neither moral suasion nor legal obligation seem to matter to them. The only sense in which they "have to" do anything is the sense involving physical necessity.
It would be a catastrophe if we lost our sense that there are certain things that our government just cannot do, where "cannot" means something more than physical impossibility. Imagine the possibilities: we normally think that the President "cannot" just shoot his political opponents. But surely in one sense he can, at least if he's a decent shot. Maybe he couldn't do it without being thrown in jail. But that's not right: surely in one sense he "can" bribe the judges, suborn perjury, impose martial law, or do something else to get himself off the hook. Do we really want to go down this road? I don't.
The Bush administration threatens us with the catastrophe of losing our sense that there are things the government cannot do every time they do one of those things. I never, ever want to go along with their redefinition of what is possible, which is why I refuse to stop being outraged when something like this happens. (It's also why saying: hey, why are you still surprised? is beside the point. I'm not.)