Iran is not stupid enough to engage our military openly. We would annihilate their military in about 5 minutes.
Unfortunately, that assumes that the Iranian leadership (which, of course, controls the military) is animated by
rational decision-making.
I simply do not believe that to be the case.
Rather, I believe that it is animated, 100 percent, by an apocalyptic zealotry, that views the ushering in of the long-deceased Twelfth Imam (or Mahdi) as the most glorious event possible. (It is sort of a perverted version of the Christian Parousia.) And if that can best be accomplished by beginning a war that would ultimately kill hundreds of millions of innocents, well, the Iranian leadership views that as a genuflection in the direction of The Greater Good, I believe...