I hope this manga doesn't end with
"We figured out a way that no one has to fight ever again and we can fix the earth!" At most they reach a point of indefinite sustainability for the survivors. It would spit in the face if the sacrifices made beforehand and a naive and unrealistic message of realities of war and struggle. Because sometimes you do have to fight to survive even if there isn't a 'bad guy' that really deserves it.