The US still has a huge nuclear arsenal, more aircraft carriers than the entire rest of the world combined, more advanced fighter jets and bombers than anybody else, incredible logistics, etc.
Make no mistake: the US might not be able to beat an asymmetric insurgency (mainly because that's just fundamentally not how that works -- attacking them only radicalizes more insurgents) when a moderate who at least somewhat cares about things like the rules of war and not becoming an international pariah is in charge, but that does not mean it isn't capable of totally exterminating the entire population of an enemy state without even breaking a sweat when a thin-skinned fascist dictatorial madman is in charge.
The US has become considerably more dangerous to the rest of the world, not less.
No, that's factually incorrect. The only purges of the military that have been happening are of trans people and some "disloyal" (read: actual patriot) top brass. While trans people may indeed be among the "best operators," for all I know, they definitely would not have comprised all of the "best operators" simply because there weren't enough of them to fill up that category to begin with.