Perhaps you have heard of mutual assured destruction. If Iran acquired nuclear weapons, they will never use it against Israel or any other country. Because they know retaliation will be swift and immediate by the US.the fact we must watch out! should remove all doubt that Iran's nutjob leaders must never be permitted to acquire nuclear weapons
If they ever managed to exterminate Israel they would soon turn thier attention to the West and the Great Satan
For reference, see North Korea. Despite all their bluster, North Korea is not dumb enough to use their nuclear weapons against the South.
But given that Iran has been attacked twice in a year by US and Israel, they will be stupid not to race to acquire nuclear weapons. Because, they would not have been attacked if they had nuclear weapons.
BTW, you seem okay with Israel having nuclear weapons but not Iran








