War supporters acknowledge that things could go seriously wrong. Their argument essentially is that the status quo also had risks, and that the war at least creates hope for a better future.
But hope, as the saying goes, is not a strategy, and it is perfectly possible that the regime could have evolved into something more acceptable in the face of regime division and public pressure after the natural death of the Supreme Leader. If you respond by saying that is also a strategy based on hope, I would note that it at least doesn’t require a war.