The US and Soviet leaderships were composed of sane men. That is not the case in Iran.
If it would be an effective attack it’s a good attack for sane men to plan to use. 1 nuke blown high takes out your enemy, with actually fairly low bloodshed, sounds very sane; especially when compared to the nuclear war plans that actually did exist. But they never came up with this plan. So clearly it’s got issues in the execution portion. So maybe it does take an insane man to plan for it, but not insane because it’s so destructive, insane because it wouldn’t work.