Friends, one of the issues that helped me better understand the general behaviour of humans was their social structuring, derived from the behaviour of herd animals and their peculiarities.
Many people feel almost offended if it is said that we came from the monkey, or that we are simple animals more developed than others.
-- !Our desire to be superior beings clouds our mind!
But it is this way, and if we want to study ourselves honestly, we must to know ourselves more deeply:
Many of the peculiarities and human behaviours come from having belonged and been framed for millennia in herds or social groups, which and to form a structure or herd, had to be commanded by chiefs (the strongest) and ready to fight and defend us from rival packs.
*Therefore, here the instinct of personal self-defence is extended to the defence instinct of the group or herd built:
"Each pack defends its components and obeys the leader who leads them."
Naturally, each herd needs a territory to live and forage in (humans need a tribe, country, nation, etc.).
Humans, a little more developed, also need community laws and customs, social ideals, religions, political ideas, etc., as we advance in our development.
That is to say, as we develop mentally, we also form more and more types of groups, clans, teams, etc., and in all of them there is an underlying idea or instinct of struggle and competition for the space and privileges that society is achieving.
But we continue to behave like herd animals, with our group of component comrades, and also our bosses.

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Now, all this competition and development of groups and societies can be positive, always without exceeding certain limits of coexistence.
But no, sometimes it happens that certain groups, races or nations take their archaic tribal or herd animal feeling to the limit that they fight and eliminate their supposed enemies.
That is, individuals with such extreme tribal sentiments take power that they fight and eliminate all races, religions, ideals, and people who are different from their "herd".
And so we see characters as "archaic, extremist and retrograde" as Hitler, Pol-pot, etc., including religious groups that advocate the Holy War against the infidel, who acting as true beasts destroy everything that does not belong to their herd.

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But the next question would be:
So, where should we direct our future aspirations?
Well, since we are pack animals, let's use that quality to become a single pack of humans, respecting the peculiarities of each individual (white, black, yellow, Indian; Catholic, Muslim, Hindu; etc. etc.) but feeling ourselves a single herd with the obligation to protect all its individuals equally.
And if on the way, and expanding, we can include animals and living beings, much better for all of us.