You’re correct about the current world we live in. I went to war to help our economic trading partners whose economies affected our own. Kuwait’s occupation did not directly affect us and despite the peaceful embargo threats, Saddam continued to assert his claim of rightful conquest. It was also our military stance after the ceasefire that prevented Saddam’s expansion and the embargoes embittered the Iraqis against us when we finally decided to dethrone him. History does not only consist of WW2 as an example. the same thing has been happening for millenia. Tibet and Kosovo are polar opposites of bellicose decisions. Rome fell from internal dissension and civil war when those energies could have been better spent keeping the borders secure in offensive actions. The problems we face now have always plagued empires. We just happen to be lucky enough to be somewhat isolated an our economic empire is falling apart due to our society’s inability to adapt to the fact that the world is changing.
We have to protect that empire and a soft and weak military will cause that economic empire to be taken advantage of. You can use post war Germany and Japan as examples of weak military and economic growth but remember that their economies were heavily subsidized by our military might protecting their trade from others who would take it from them. I’ll just mention the Ukraine for a contemporary example and you can research the history, both economically and politically and come to your own conclusion.