Firstly an act of war as this is, requires congress. This has not happened, therefore this is an illegal act.
Meetings between the trump administration and Iran happened just three times. The committee for non proliferation of nuclear weapons has stated this is simply not enough.
Secondly the idea of regime change would require forces on the ground. The ayotolla had already made plans for the transition of power and it's clerics that will choose the next ayotolla.
Assuming that IRG remains loyal to the cleric, which looking at the response, appears to be the case. This situation will almost certainly result in a continuation of the regime and will likely be more hard line and more determined to seek WMDs.
American assumption that the people will overthrow the regime......or they have some power play with a senior member of the IRG....again if a official is willing to be bribed to work with the yanks then honestly the next regime will be corrupt
I've worked in Iran, not everyone hates the regime and those that do many don't like American foreign policy either. It's a delicate situation that needs skilled diplomacy.
A war in the middle east will once again drag us into protecting our assets, our people. It will drive inflation and damage our economy. Tourists will have a target on their backs and places like Turkey will suffer greatly as tourists seek safer places.