Are we all really one?

Some how everybody low key hates  everybody  and think they are better and more special than every body in the world, I'm not sure if hate is the right word tho  but from my experiences it's definitely not love.

We see this both in races, religion and also in our general beliefs.

Why do we humans in try to distinguish ourselves at any point in time.

The white man some how thinks he's better than different from the black man, the African American thinks they are better or superior to Africans living in Africa.

Nigerians living in Africa thinks they are  better or more special than every other Country in Africa.

And even here in Nigeria the average Igbo man thinks they are special and better than other tribes in Nigeria, same thing with other tribes, they'll think they are better and more special than each other.

Coming down to the Igbo people, The Anambra man thinks he's better and more special than people from other states in the south east, same thing with people from those other states too.

As an Awka man, the average Awka indigene thinks he's better and more special than other people from other towns in Anambra or Igbo land in general, same thing with other towns in igbo land.

Why do we'll think we are better and more special than everybody else?

I also think this is the major cause of disunity in world today.

what do you think should be done about this or do think its the human nature and nothing can be done?