Here's the problem, Ron. We currently have no way to identify a signature from a detonated nuclear weapon. If a nuke is detonated against a US target, who do we retaliate against if nobody claims responsibility? And, Iran is indeed "stupid" enough to attack us. They really do believe that the chaos brought by nuclear war will hasten the Mahdi, a sort of Muslim messiah. This concept is very difficult for the Western mind to comprehend. How could religion, which we have relegated to a quaint, minor role in our lives, so motivate modern men to bring such death and destruction on their own nation? But if you are willing to accept the words of Islamic leaders in Iran and elsewhere, you will see that they are indeed so motivated.