True, this is why the US likes proxy wars, but wars offer net benefits to the heads of states in the form of fear, propaganda, divide and conquer among your own people, a pretext for increased state power and surveillance, and ultimately, of course, you come out the other end with the state granting itself much more control.

This is why in 1984 "we've always been at war with Eurasia."

Even from a purely economic perspective, the military industrial complex is in the US. War is good for business.