Good points. And yes. Why would Iran want to have any armed conflict with us unless they where certain their someday crude atomic weapon would actually work, in order to use it as leverage.
Most likely they don't. They would hope their bluster would keep the Euros and Americans out of it so they can deal with their more local goals as they wish. But, they may be miscalculating just like Saddam did with Kuwait. I say maybe because things just aren't clear, like everybody is hoping this problem will just go away.