@deshipu Name three. I can't think of any. Thousands of years is a long time.

Not to mention, if we're debating fundamentals of choices forced by competition, we'd have to include economic warfare in this too. For example, the whole world has been mostly peaceful in the last few decades - but that doesn't mean countries get along nicely with each other. They just beat each other around with trade, treaties, tax law, etc. and so far nobody is pissed enough to start a major war in response.