Using the current volunteer format you're correct. I'm not one to think a draft is on the horizon but, should military action be required against Iran involving the US, we would almost certainly have to utilize a draft.

The upside, however, is that Europe is heavily involved. They would also carry a significant portion of the military load.

The downside, as has been pointed out, is that Russia and China will probably "back Iran's play."

Should be interesting to see how this all plays out. I imagine sanctions are the next move.

I don't know how easy it is to transfer the technology used in nuclear energy to nuclear weapons. I imagine, though, that the two are close enough to where once you possess the technology to one the other falls in line.

I imagine the West is afraid of allowing for Iran to acquire nuclear technology and materials for energy and then one day making the decision that the IAEA is no longer welcome in the country.

This is almost like a kid and a car. Europe has offered to sell Iran the necessary materials to produce nuclear energy ("borrowing the car") but Iran has insisted they be allowed to develop and produce their own.

As I mentioned before, it doesn't help Iran's case of "peace" when their leader, even by members of his own government, is seen as a radical who has alienated the country in recent months from the rest of the world.