>because the US spends so much on its military, its allies do not have toThe US also doesn't have to spend so much on military considering it has no enemies at it's borders. It can always ramp down and spend the extra on social services. Ask yourself why doesn't it do that?
>but it's a great way for allies of the US to prosper under the might of the US military while maintaining security in this regard
Oh please, stop being so generous with your allies, you don't have to. You have this a bit backwards.
It's mainly the US who prospers from the oversized military. Do you think the US would stay the world reserve currency and as influential on the world stage in terms of decision making, if the US had the military the size of Denmark? It's precisely that powerful military that allows the US to dictate a lot of international terms and deals in its favor: "Oh, you're a commie nation with different values than us? Then enjoy our globally imposed embargo and sanctions that will impoverish your people."
The US could save a lot of money by shrinking its military and global influence to just cover the US/NA instead of the whole world, but then that would leave a worldwide power vacuum that China will gladly fill and that would also make the US less influential and therefore poorer.
So you see, the US spends 'hella stacks' to be the world reigning superpower because it profits more than it spends.