Context (for those who don’t know): Israel and Palestine
Even animals patrol and defend their territory. Why should human be any different? If anything else, borders are an improvement over constant skirmishes and raids where two different ethnic groups meet.
EDIT: Interesting how you completely ignored the “Borders are a solution to constant ethnic clashes” part of my comment
The animals argument is bad. We are animals and the idea is to refrain of our bad instincts in favour of the greater good most of the time.
That being said abolition of borders is a very bad idea, a very basic visit of human history will squash any misplaced idealism regarding that subject.
That also being said immigration is most of the time a good idea as long as you put a consideratr effort into integration for your newly minted citizens.
Now I realize most of those are opinions without substance, the idea is to realize where people push back and why before backing them up.
The reason ethnic clashes are happening in the first place, is because there was not enough intermingling between neighbors, in big part because people like you thought humans aren’t smarter then animals and should be separated.
Humans aren’t smarter than animals because we are animals. We’re also not smarter than non-human animals either, as evidenced by our self-destructive behavior.
Animals kill and eat their young. They roll or eat shit. They rape. You sure that’s the argument you want to use here?
“animals do it why shouldn’t we” is one of the worst reasons to do something. Animals are literally dumber than us.