There's really no one that can touch the US armed forces with numbers, training, technology etc. And before you say China & Russia, they don't even come close to the numbers the US has. With any start of a war the B2 bombers will go first, they'll decimate all their SAM and radar sites, then the air force goes in and wipes out any airborne threats. After that it's up to either the Navy (depending on position of their aircraft carriers) or the air force again in destroying key command buildings. Finally once most of the threats have been neutralized they'll send in the Marines + Army to clean up the ground.
China has an up and coming modern air force, but it can't hold a candle to the US.
Russia as well (they might have a couple of hypersonic low level missiles) but they're not ready and you must be joking to think that the US doesn't have something better or can eliminate them. Hell the US has 1,000 F-16's, 300 F-35's, 450 F-15's, 200 F-22's (which can take on 3-1 F-15's and win) 1000 F-18's, 2000 UH-60 helicopters, and about 200 heavy bombers etc available. And those are just ACTIVE.. that excludes stored aircraft. The numbers are mind boggling!
This is why you can't compete:
Military budgets: (and the US has been like this since WW2) in fact you could add up every country under the US and they'd be about the same! lol
US : 738bn
China : 193bn
India : 64bn
Russia : 60bn
UK : 61bn
This is why it is pointless to have an armed force when the US is here. It's like throwing a hamster into a cage with a lion and thinking the hamster can win...