That is not quite entirely true, war -- especially long-term -- results in huge funds being funnelled towards things that can blow up the other guy, which can then move into more peaceful realms. Not to mention the requirements for research safety and grants are often quite different.

Without WWII, would we have operational jets in the early 40s? What about rockets? All of rocket science from the late 40s and early 50s came from WWII germany. Likewise for fission and fusion research, how much longer would it have taken without Los Alamos?

> Competition invites advancement, blowing up your competitors does nothing.

That's crappy pop-history that's largely been discredited. Inventors generally don't need motivation, only funds (of time, of money, of equipment, of relations). And the reason for those funds and where they come from is the lowest of worry, as long as they are provided. Competition is irrelevant to invention and advancement.