A common argument for diversity and the inevitable racial mixing suggests that once we achieve one world grey race, the conflicts between races will erase themselves. This parallels pacifism and the argument for egalitarianism, which is that when all are equal, causes for disagreement will vanish.
To an experienced mind, this makes no sense, since conflict drives change and hierarchy is necessary for a functional organization of any type. Imagine a company composed of 5,000 CEOs and you get the idea why this does not work.
Even more, we can see it fail to work in democracy, which functions poorly even for simple things as twelve co-workers choosing where to go for lunch (hint: you always end up at Olive Garden). When the broadest segment of society makes decisions, you get low-quality decisions.
Pacifism fails because it changes our focus from forward-achieving results in reality to maintaining a fragile compromise. It is as if people in a car decided to focus on who had the most time at the wheel instead of where the car was going.
In this way, it parallels strong centralized systems like Communism, which make people dependent on government for their thinking, and therefore infantilized and unable to respond to reality without some framework granted to them by an external source upon which they are dependent.
Along similar lines, the argument for one grey race that without racial differences we will embrace pacifism also fails because people simply find other divisions within their society:
Results indicate that people in the lightest skin color category have an average of 1.4 additional years of schooling and 53 % more in hourly earnings than their darkest-skinned counterparts. Social mobility is also related to skin color. Individuals in the darkest category are 20 percentile ranks lower in the current wealth distribution than those in the lightest category, conditional on parental wealth.
Lighter skin color suggests a non-primitive creature more capable of abstract thought and complex analysis. Naturally, in each racial and ethnic group on Earth, a hierarchy emerges, and lighter skin color signals higher status in that ranking.
If not skin color, probably something else. Egalitarians keep trying to defeat the idea of social order, or separation into roles, which requires that some take up leadership roles. In fact, we need hierarchy, but a less broken version than we currently have.