So explosives automatically means nukes to you. You have quite the imagination it seems. My point is if Iran sees fit to sponsor suicide missions with REGULAR EXPLOSIVES, why should we put it past them to attempt a suicide mission with a nuke in one of our cities. Do you think our borders and ports are so secure a nuke could not find its way into our country? Tim McVeigh seemed to be able to drive a bomb the size of a Ryder truck up to a Federal building undetected. A nuke won't have to be placed so accurately.
Sure, they can deliver it into the smoking ruins of our economy and society when they finally have the capability to do so. I find it difficult to focus on a threat halfway around the world that may or may not come to pass, when there's a semi truck barreling down on me in the next lane.