Stunning to think of. The US military budget in 2012, which does not count military related costs borne by other agencies which effectively double or even triples the number) was $729 Billion. For a world population of 7 Billion.
So the US spends somewhere betweeen $100 and $300 for defense related costs for every single human being on the planet today.
Or even more stunningly- anywhere between $2,321 and just under $7,000 for every single man, woman and child living in the United States.