You are exactly right on your arguments. The PR was lost by Bush, and its has taken its toll. However, the realpolitik of the situation is that this will not end up like North Korea, where a family of luntics rules and threatens us decades later.
I think you've got that right.
I see this as a paralell to WWII. With Iran as Germany and Syria as Italy.
Iraq, to me, is like the Spanish Civil war (or Algeria, someone else pointed out -- altho now I'm going to have to go research that).