Here is a paradox, we are all the same, yet we are all different. We all have two legs, two arms, two hands, one head, one nose, two eyes and two ears (at least that’s what’s considered “normal”). But, we are all so different. Our experience of life affects our behavior and our interactions. Each one of us is unique genetically and experientially. Even “identical” twins try to distinguish themselves one from the other.
We now know from studies of twins reared apart, that nature (i.e genetics) plays a greater role than nurture (i.e. the environment) in the detemination of our personality and behavior. But, the environment, how we are treated by our parents, our peers and others, has a tremendous effect on our lives. An orphan or someone subjected to violence or war will be phsyically or mentally scarred compared to another who is similar but has not been so exposed. So the paradox is there, and to the extent that we are the same and different we compete with each other, for jobs, for spouses, for income. That’s basically why communism and other forms of intense social sharing in the final analysis don’t work, that’s why the kibbutzim in Israel can never be more than a small percentage of the population and why Communist China is reinventing capitalism.
Skin color makes such a difference, especially if you are born in a society where the majority of people are a different race. Sex also makes a huge difference (vive la difference), but women and men differ greatly among themselves in relation to sex. Although belief system makes a difference, it masks the true differences which are ethnic and genetic. Basically hatred comes from these small differences, how one tribe or national group tried to compete for land and resources with others. But, many conflicts today are more civil or tribal wars than inter-national conflicts.
Almost all the land of the earth has already been divided up and now its a struggle for supremacy within those lands; Hutu and Tutsi vied for control in Rwanda and Burundi, Arabs and Jews for Israel/Palestine, Alawite and Sunni in Syria, various groups in Somalia and so on. Some countries were artificially created by the colonialist powers, such as Lebanon, Jordan (Transjordan), Iraq and so on, and some of these are failed states. Others have fluctuated in size with time and conflict, such as Romania, Hungary, Armenia, Sweden, etc. Very few countries are completely homogeneous, Japan springs to mind (but they wiped out the Ainu). In the final analysis each country must find it own way to inter-tribal peace and stability.