Killing brethren

Remembering the past, 65years ago, after the Pacific War, US insisted to occupy Japan not under the condition of divided control by Russia but that of US single control.
Thanks to the clever selection of US, we Japanese need not kill each other because of different ideologies.
Korean people are so miserable on the other hand as to fight with the same nations each other. The enemy is the same races, the same nations and speaking the same language, incredible?
Shooting howitzers each other are nothing but a destructions nor killing brethren.