User blog comment:B214/Talk About What You Want! 3/@comment-74.58.219.123-20150618191740/@comment-24098614-20150620004408

It is to be expected in what they did this scenario was played realistically to what in the real world was like because both sides have fought in the past, and have held grudges and hate towards each other, and quite  a few of them didn't want to end the status quo.

The death of God in Dxd created a opening to change this because if both leaders of Heaven and Underworld were still alive the war would have continued for a eternity, and you would see a endless cycle of hate and war.

This is why I considered Sirzechs a cool character in the story because as the Maou he could have continued this cycle against Heaven but he has seen enough bloodshed and violence due to the Civil War that he was part of, and he desires for the Underworld to be at peace because if they continued this the entire race of the Devils would have been wiped out.