Why don't we attack Iran?

I am confused, i thought we attacked Iraq, because, um, whathisname(sodamninsane) supposedly had nuclear weaponos (cough, cough), so Iran SAYS they have them, they are going to use them and we dont do nothing about it. Am I to understand that we attacked Iraq because of the exact same cirstance, but wont attack Iran? Geez, too much work, not enough beer, toooooo much confusion. Most money wins, right? Or who is sleeping with who? BLAH!!!!!!