I think it's slightly more nuanced than that. The US military has spent decades and trillions of dollars training and preparing for
exactly what they're doing now: blowing shit up on the far side of the planet on short notice without risking too many deaths of their own service members. Important parts of it are broken - like, say, maintaining ships, and forgetting that sometimes opponents
can shoot back (airbases don't get stealth coatings), but on the back of that time and money investment, they're still (1) pretty damn good at it - almost certainly better at it than any other military. Iran
can't stop those planes and cruise missiles flying overhead, and I'm not sure any other country could either.
What seems to be entirely missing - and, as you say, has been for a long time - is the recognition that this isn't the same thing as
winning a war. I'm honestly fed up of listing all the wars since pilots started chucking grenades out of their cockpits where airpower has failed to live up to the idea that it could achieve victory just by itself: there is
at most one (controversial and debated to this dayl) success in a literal century of unambiguous failures.
Until Trump, US presidents have done two things "right" about these wars of choice:
- They offered some kind of political goal that motivated war rather than other forms of diplomacy. Those figleaves could be wafer thin, to mix a metaphor, but even Bush II went to the effort of faking up a bunch of intelligence about WMDs
- They picked wars of choice that, if not won quickly, could "safely" be dragged out for some other president to quietly admit defeat without risking catastrophic consequences (although JFK and Reagan were both really close to crossing that line).
Iraq and Afghanistan turned into seeping wounds that bled blood and treasure for decades, but they weren't really costing
America very much (let us say naught of the successive crises that the resulting waves of refugees have triggered in Europe and the middle East: from the perspective of the USA, Somebody Else's Problem).
The problem with Iran is not that the American military is more or less toothless than it used to be, but that it has the ability to fight back in a variety of ways in which the US military has no, or limited, response. UAVs are part of that, but the biggest part is the Strait.
War for fun and profit has been a losing prospect pretty much since not long after the start of the industrial revolution: the trio of the Crimean war, US civil war, and Franco-Prussian war really drove it home. Off the top of my head, the
only war since then that has been a net positive for a participant was the second world war, in that it systematically crushed
every single industrial competitor to the USA while "merely" being severely uncomfortable to them. As with the airpower-winning-wars debate, that's a pretty slender evidence base on which to base a new policy of the war paying for itself!
(1) It remains to be seen if they will still be capable of it
next time: arsenals that took decades to fill are emptying in weeks. The performance is likely to be less impressive if "next time" happens before cruise missile and interceptor stocks can be rebuilt.
Maybe the USA has a
Lloyd-George in waiting, but it doesn't exactly look likely today.