That's exactly why we're seeing all the provocation these days.
Our enemies in the middle east believe that we won't do them as we did Japan, or Germany, for that matter, not that we can't.
Mostly agree, but we in the middle east are in much the same position as Hanibal in Italy 150BCish. We can't be beaten but we can't prevail either. Not enought troops on the ground for a general war in the middle east. Iran knows this and just might be willing to roll the dice, if it could come up with a good Perl Harbor type attack on US forces in Iraq. Not likely, but it is a worry.