Humankind's deep desire to remain divided

Growing up, i lived in many different countries. I've been part of the majority in some and part of a minority in others. The one human behavior i always found fascinating across many cultures is people's putting themselves in groups. but then even within these groups you find people segregating into smaller groups and smaller groups. and there is always this tension or animosity among groups.

well first humans segregated into countries and regions cuz sharing the planet was too hard of a task for us. How can the Asian, Africans, Americans and Europeans possibly get along. but it didn't end there. Let's take my home country of Egypt as an example as not to offend anyone. well now we were segregated and are now Egyptians. hooray!!! but wait now you're either muslim or christian. but all is not well yet. what sect do you belong. where exactly do you go to worship. many will say yes religion is the problem. but that's not true. there's ethnic segregations. are you coptic, arab or nubian? but then what tribe do you belong to? and u might think that tribes was as far as it goes but nope. then you get asked well which branch of the tribe do you belong to and on and on it goes till you're the only one left.

 the point i'm trying to make is that people who think that if we only get rid of "these people" everything will be fine are wrong because there will always be something we can find different about each other. instead of looking at the many things that make us different and unique we should look at the many more things we have in common with each other. 
 

 just something i've always thought about.
 

Opinions??