Seen lots of data points like this on the abstract question of Iran getting nukes:
So the “why should we care if Iran gets a bomb” crowd may have a large online voice but are definitely in the minority.
Question then becomes how far we should go to produce that outcome. I’m personally very comfortable with a B-2 dropping a MOAB or two on Fordow to seal the deal, especially now that the air defenses are gone, and Iran’s proxies have been largely defanged. Pretty sure that’s going to be a politically popular position with the average American as well. We don’t like Forever Wars but we don’t mind the isolated air strike with maximum value (see, e.g., Soleimani, Qasem, Zawahiri, Ayman-al, etc.).
I’m much more agnostic on regime change, as much as the mullahs would deserve it karmically for what they’ve done to that country. I tend to think that what comes after would be better than the status quo, but that’s at best a 60/40 proposition. We shouldn’t be involved either way. The value of preventing them from going nuclear means we don’t have to pay attention to them any longer and can focus limited military assets in the Indo-Pacific countering China.