While I somewhat agree with your statement, I would be
HARD-PRESSED 
to believe the US, doesn't have "cutting-edge" military tech, we just haven't wielded yet. We went to war with those "goat-herders" with our basic weaponry, IMO. I'm sure our military would "pull out" if we had to go to war with China or Russia. They're well aware of the numbers/population advantage those countries have, alone. Stealth came out in the 70s.
The Nuclear bomb, in the 40s or 50s. WTH do you think they've invented since then? Mind you...you see the military budget on a yearly basis. The US plays coy when it comes to real war, until it's time to go frfr. I'd argue all these unexplainable UFO sightings defying physics, (throughout and around the US), is unreleased tech, from our military.