That's why I'm not so upset with the Iran situation. The American government will face so much damage from this (economic, militaristic, political) that their appetite for war wouldn't be much (for a decade perhaps). At least that's my opinion after looking at iraq and Afghanistan.
This obviously changes if somehow the Iranian people topple the theocracy without American boots on the ground. This is definitely what the us admin is hoping for (and getting the shah back), but this looks... difficult...
Once American boots hit the ground, it's just another Iraq. So many factions and separatists sitting in Iran rn, who are being suppressed by the theocracy.
Also, the theocracy was arming, training and supporting islamist fascists in the neighborhood for decades. Will remnants of this regime just forget how to do that in their own country?
Again, this all hinges on the will of the Iranian public. How hard are they willing to fight for democracy? Will they get rid of the theocracy? Will they resist the terrorists? Will they resist US pressure to reestablish the monarchy? How do they deal with the separatists? Does a sentiment of war take precedence over a sentiment of "stfu, please stfu and keep the peace, we're Iranians, war is bad, peace is good, please please just stfu"?