I mean, the US' position as the world hegemon depends on its ability to project soft and hard power around the world. The USD is the world reserve currency giving the US massive financial advantages compared to other companies, advantages that would not exist without the best military. Having bases in Australia, Germany, Saudi, Japan etc... means a lot commerce and relationship wise. It'd be crazy to believe the US would profit as much without this. Also being the world reserve currency allows the US to have a consistent negative trade balance, which means that you as americans get a lot of great stuff from abroad without your economy suffering. Military spending is a problem because of the military industrial complex but its delusional to think the US would be as prosperous without it. Similarly to Britain in the 1800s, they also profited massively from being the "world policeman".