If we do things my way, sanctions may force Iran to negotiate sincerely and permit FULL IAEA inspections. In this case, not a shot is fired. This is the best scenario. OR, if Iran refuses to cooperate, strikes occur on nuclear facilities ONLY. The oil fields (Iran's primary source of income) are left intact. Civilian deaths occur, which is bad, but they are confined to the nuclear facilities. No civilian city centers are hit. Iran is humiliated but otherwise remains able to function as a nation.
As it stands now, Obama and Netanyahu are trading blows over action against Iran. Obama has barely managed to keep Netanyahu at bay, and purely on the hopes that sanctions will work. Thus, Obama has been able to keep the peace. If we do things Justabubba's way and permit Iran to develop nuclear ICBMs, we have a 100% guarantee of hostility by Israel. Why would they? Because they know they can take out those nukes with a quick strike, and Iran would be helpless to stop it. Iran would be at their mercy.
Remember that "mysterious explosion" at Iran's missile facility? Nothing showed up on radar, no enemy aircraft invaded Iran airspace. The missiles just "spontaneously" blew up. Guess what, JDAMs or cruise missiles can do exactly that. They don't show up on radar (JDAMs too small, cruise missiles fly under the radar). Iran's "nuclear deterrent" disappears in a flash, and nobody knows why...and least until Israeli aircraft come streaming in out of the sun prepared to dismantle the Iranian military. Israel has the weapons to do this. Israel hasn't attacked Iran, but letting Iran have nukes is a sure way to make it happen.
In short, if we do things as they are, we have the possibility of No Conflict, or Limited Conflict. If we do things Justabubba's way the ultimate end result is: Maximum Conflict.
Lastly, nuclear-armed nations have in fact, attacked one another directly. in 1999 (while both India and Pakistan possessed nuclear weapons), Pakistan felt they could attack into Indian territory. They felt the concept of MAD would prevent a nuclear exchange, so then conventional attacks could happen without nuclear reprisal. Even with nukes, war happens anyway. Even then, the superior conventional military wins the day.
Indo-Pakistani wars and conflicts - Wikipedia, the free encyclopediaIndo-Pakistani War of 1999 (minor war): Commonly known as Kargil War, this conflict between the two countries was mostly limited. Pakistani troops along with Kashmiri insurgents infiltrated across the Line of Control (LoC) and occupied Indian territory mostly in the Kargil district. The Pakistani government believed that its nuclear weapons would deter a full-scale escalation in conflict but India launched a major military campaign to flush out the infiltrators. Due to Indian military advances and increasing foreign diplomatic pressure, Pakistan was forced to withdraw its forces back across the LoC.