O.K. let's look at this puppy from their point of view and see if it holds water. Let's just say they have a nuke and want to use it. How would they use it? Before it ever went anywhere it would be blown up over Iran, killing them. Even if they got one off and it landed, where would be the target. Say they get one off, it landed, blew up, at this point I don't think that 100,000 strong would be enough because we would wipe everything they have off the map. No Iranian would be safe in America. Let them and others think about that and put it in their pipe and smoke it.
Would they need to detonate one in another country for it to be effective or just announce when & where they're going to set one off so they get the world's attention then come out and say "We have another nuke planted in a major city and if you don't give us "X" we'll detonate that one too."?