What about the microwave oven and the thousands of other products the military has indirectly created?
It isn't military that's in question. It's their engagements.
The U.S defense budget would be a fraction of its budget if used for defense.
There is an upside in wining wars. But since the U.S has been losing them, it's funding jobs that provide no value. Would better be spent elsewhere.
The Japanese unique economic boom after WWII was mostly due to having little to know defense budget. Germany's was less impressive but also benefited from focusing on the economic performance.