The big picture is that unless the human race has some grown up and serious conversations about our species then we will never solve problems like hatred between many of us.
First, we have to acknowledge our faults.
Us humans can soon descend into behaviour similar to our primitive ape cousins, only worse.
We are inherently a herd species and fiercely territorial.
Yes, we have sophisticated many of the so-called animal traits to some great extent but they soon appear when given the opportunity.
We can draw maps as much as we like but until we develop individual self-responsibility and follow our own judgment, we will continue to herd together is whatever groups we are born to, follow, believe and trust whatever the pack leaders tell us be in race, religion country etc etc.
Its getting close to the time when humanity need to wake up and look for solutions.
I’d start with making all world leads women – They are less violent by nature. Banning religion for example wont help as we will just find another way to group together and look for a enemy.
Otherwise, unless we want to wait for thousands of years by evolution if we survive without destroying ourselves then it has to be genetics. Edit out those genes that make the males especially prone to dominance and violence.

Of course its fantasy to reason it out because at the then of the day we like killing each other, honestly... yes we do
Why are the most popular games us boys play about killing some percieved enemy.