Why nations fights ? What would be the problem between two people who don't even know each other.There are thousands of kilometers between them. They will probably not see each other all theirs lives.
Let us see what is the problem in this system.
The problem is a mistake in diplomacy.You just cannot give that major decision to bunch of selfish human(evolution says, I don't).
You wake up one morning and one sassy, irresponsible guy wants you dead.This is not fair.Who are you to say who will die.
Human nature inclined to competition.If you feed this impulse with ignorance the result will be WW III.