Another interesting fact is that most of what the military does is "support" for the few people at the pointy end of the stick. I.e., the USAF has 330,000 active duty personnel, 150,000 civilian personnel, and about 5,000 planes. That works out to about 100 people per plane.
This isn't inefficiency (per se), it's just that: (1) complicated, cutting edge systems need a lot of maintenance; (2) there are a lot of indirect mission-support type jobs (photo reconnaissance, radio intercept, decryption, ground control, cartography, weather, etc.); and (3) someone has to make sure that all of these people and equipment have food, water, ammunition, spare parts, etc.