This is a question I ask because I have noticed that in other areas of nature there are species which hate each other's guts!
In the plant world there are some plants you should never plant together. They will end up either destroying themselves, or one of them will destroy the other. For example, when I planted a biennial Angelica plant next to a tall slow growing Rosemary bush I lost the Rosemary bush in no time. I know that Rue should not be planted near other plants, and there is a history of what is termed "complimentary planting" whereby some plants help protect others from diseases.
There are also some animals that do not like being near each other. Within the bird kingdom I have watched as robins chase away sparrows. Magpies are hated within the crow family. Seagulls and crows do not get on at all, with the seagulls searching out the crows' eggs.
With so many plants not getting on with each other, and even birds, never mind the usual cats chasing birds and mice, I believe there is an inherent "hatred" or "despising" of similar animals that is not easily overcome.
As a species, the human race has always "hated" or "fought" other humans, usually on a tribal basis, often due to a lack of food, water, or land for the tribe. But we are today being encouraged to "get on" with our human neighbours, and I wonder sometimes if this is truly possible in every instance?
I accept that skin colour does not have to be a problem, even other cultures can be tolerated, but I have found that the people who prove themselves most friendly and tolerant are those who at that time adopt a similar culture/society and language. Not every part of the globe should be under the same culture/language, as long as we acknowledge that in a particular place a certain set of rules/culture/language is dominant. In fact the diversity makes it pleasurable to wander, as a guest, in other places, and even become resident there as long as the dominant culture/society/language of the area is adopted.
Perhaps, what makes us "hate" each other is not the physical differences of the human race but the cultural differences that each country/tribe/nation adopts.
I have watched over the past few decades the British and English identity be subsumed and overtaken by other cultures/languages/societies. It is the same piece of land, and the same environment as far as nature is concerned, but the governance of the society within the UK has allowed others to come in and take over the dominance of the culture/language/society. This is causing a lot of heartache for many indigenous people.
I accept that in the past many people have come and taken over this island. The Romans, the Saxons, the Vikings, the Normans, and each has put its stamp on the land, but they did so by military conquering, not this slow yet forceful stealth takeover we have experienced in recent times. Betrayal by the powers that be is how some people have viewed it, and I can understand their reasoning.
But I also wonder if we are meant to "get on" with our human/tribal/national neighbours?
It is a question that will rarely be asked, but perhaps it should be considered, even quietly, so that when people discuss diversity and equality within society they truly comprehend exactly what is meant by these words, and the consequences that they engender.