My understanding is an strong possible alternative to the Islamic State of Iran is a Communist state. Not a great improvement from my perspective.
There is no reason whatever Iran cannot have a democratic and pro-American government. It had one for decades in living memory and it can again. If there are a million rat-bastards between where we are today and that outcome, we should murder a million rat-bastards and get there.
Some things are too simple for moral idiots to understand. The rule of jackasses cannot be justified by the existence of other jackasses.