> 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.