The air force of the army of the US navy (i.e. the air force of the USMC) is bigger than the air forces of all but 3 countries in the world. It's the 7th largest air force in the world, only beaten by the actual USAF, the army's air force, the USN air force, and the countries of China, India and Russia (though that last one might be out of date thanks to Ukraine).
The US might not be quite as powerful as it's sometimes portrayed to be, and might really struggle when it faces tactics that it hasn't prepared for. But, it's still a ridiculously powerful military.