It depends a lot on the kind of campaign that is fought.

The US had complete air superiority in Iraq and Afghanistan and while it helped it is unclear how it would play out in a drone-heavy battlefield.

In Afghanistan for example the assault on Shah-i-Kot Valley and the ineffectiveness of air support is instructive https://en.wikipedia.org/wiki/Operation_Anaconda#TF_Rakkasan

It's worth noting that the US lost both those wars - the Taliban rules again in Afghanistan and Iran is more influential in Iraq after the fall of Saddam than it was before, eg: https://www.cfr.org/articles/how-much-influence-does-iran-ha...

> The problem in Ukraine is that anti-air defenses control the skies... <snip> ...US forces can fly relatively cheap bomb trucks anywhere and drop ordinance on anything. Stealth aircraft and NATO doctrine apparently work.

In Ukraine, neither side has access to the air weaponry (in capabilities or volume) that the US does - so the battlefield has evolved into one of drone superiority.

So yes, the US could (logistics willing) pummel Iran with B52s, B2s, and the like, maybe largely unopposed. However, this would only achieve so much: "winning" would be very different, especially when it's likely to turn into into a grinding resistance/insurgency ground war. A better analogy than Ukraine may be the Russian invasion of Afghanistan in 1979, only Iran has far more trained fighters and weaponry from the start. Or Vietnam, of course.

Maybe the US could "win", but it would depend on the strength of the political will to continue losing soldiers and spending huge amounts of money; and it would certainty be seen as a "forever war". And of course (as noted elsewhere) the US' more recent forays into Iraq and Afghanistan show how difficult regime change by force is.

There is no political will in the US to spend billions of dollars and institute a national draft and have tens of thousands of soldiers dieing. That would probably cause Vietnam War-style protests if not an outright civil war

Iran is a large country, just getting to Tehran with large-enough force is logistically enormous task.

Complicated by the fact that the logistic convoys can nowadays be trivially decimated by FPVs.

Air superiority is not going to help you much against small dispersed resistance groups with FPVs (ideally fiber optics, so not detectable by emissions from afar).

There is a chance that there will be similar democratization with AA (you will need proper AA missiles, the physics of reaching a fast jet flying high simply demands it), but the distributed passive targeting is made much simpler with current commodity computing and optics.

Achieving AA Denial is difficult, but forcing the attacker to use standoff munitions instead of gravity bombs/close-in air support not so much: shifting the risk of losing an aircraft from 1 in 100000 to 1 in 100 will do it.