From a purely historical context, I have a thesis: White-on-white crimes changed the world.
When people try to argue about black-on-black crimes, usually exaggerating "the hood" as a "war zone", just remind them that white-on-white crimes include both the world wars, which the U.S.A. originally considered to be other European wars. Europe has always hated each other, and until colonialism, Europeans trying to kill each other over borders was normal. Christianity and colonialism were ways to stop the fighting since Europeans just couldn’t get along. This country exists because white-on-white crimes. Modern warfare was not developed for this purpose. The European Union was not always so neighborly.
Now, I have not been as well-versed on other continents, so I can only speak from what I’ve learned and studied.