Diversity is a strength?

can someone explain to me how diversity is a "strength"? what exactly is the benefit of mixing people of random languages, religions, ancestries, eye colors, hair colors, height, weight, intelligence, sexual orientations, disabilities, and classes in a small localized area and forcing them to reproduce with one another? because this has never resulted in a single discovery or invention. only poverty, criminality, disease, and civil strife.

differences in people are the number one cause of war. stop the hate. separate. give every group their own land.

differences in people are the number one cause of war.

We don't go to war because of these differences. We go to war because of ideologies that perceive these differences as incompatible. Ideologies which are proclaiming the superiority of one ethnicity over another.

Even when everyone has their own place, their will still be conflicts because reality does not conform to such rigid, ultra nationalist ideas of ethnicity.

I don't think diversity is necessary a strength, but a society that promotes ideas of universalism and solidarity over rigid ethnic classifications certainly is more inventive and progressive.

For example; the early Dutch Republic, Weimar Germany, the USA in certain eras, the Soviet Union in certain times.