Are Doge, Gundo Defense Companies and Defund Ukraine Meant to Co-Exist

This isn't even a political question, as much as it is an economics one. A ridiculous item in the US budget is defense, and post the Zelensky meeting, there is the feeling that US allies should defend themselves. Hence, they begin to beef up their own defense industries. Given that Defense companies make money during times of war, and the US does not want to be involved in the battles of its allies or be the global peacekeeper, how exactly are these defense companies meant to make money other than dragging the country into war? If the goal is to stop unnecessary government spending, why should the taxpayer dollars be spent on funding defense startups founded by 20-somthing-year-olds? (not that I think their age is a disqualification, just trying to explain what it looks like to someone from the outside). Even for SpaceX, there is a non-insignificant amount of people who would prefer their tax dollars being used for humanitarian aid than space exploration.

I basically asking hwo all these people exist in the same ideological camp without seeing the inherent contradiction other than blatant corruption.