If the war, which is ongoing, escalates into open conventional war with iran, what would be the objective that would require occupying iran? If it's regime change, the iranian people are opposed to the current regime and it would only be neccessary to focus attacks on the IRGC, the political leaders--and their nuclear weapons facilities while we're at it--and it would fall. Doing that could probably be accomplished with missiles. The only reason for occupation would be to repeat the mistakes of afghanistan and iraq, and try to control the form of government that would replace it.Whose son are you going to put on the ground in Iran? Yours?
The last major tank battle we engaged in was in 91 (Battle of 73 Easting, Kuwait). We did great against the Republican Guard. But Iran is not a desert. It is also 3 to 4 times as large as Iraq. And it has allies.
A ground war in Iran is a non-starter. We'd need a much larger military. We'd also need a moral justification.
It's a loser.