There’s no absolute morality god given. Morality in every society is the result of needs of that society, the balance of forces and so on. It’s a complex issue.
War disrupts that profoundly what was morally good or bad on the day before the war gets completely turned upside down.
In Britain on the day that war was declared on Germany every German human being became the enemy of every British human being. The moral code that said that killing is a crime became suspended if the the human being in question was a German.
A soldier, previously a law abiding citizen, is taken out of normal society and placed in a new military environment, given a lethal weapon, trained how to use it and a new moral virtue becomes that soldier’s imperative to show courage and bravery in being able to do what was previously a criminal act – to deliberately take the lives other human beings.
Attempts to prescribe humane rules of warfare – not killing civilians, looting and rape have always had little effect ( not no effect) in the face of the massive switch in moral values about the taking of human life.
So hypocrisy and contradiction will abound. The British prided themselves on how humanely we treated prisoners of war while at the same time dropping colossal numbers of bombs on those prisoners ‘ families in Germany.
The enemies of the state have to be downgraded as subhuman monsters the minute war breaks out. How else would you get a normal human being to murder another one?
in Germany the work had begun when the Nazis came into power. Political enemies went first, then the Jews were downgraded to the level of vermin and all Slavs designated at inferior.
This meant that no morality or law protected the Jewish population or those in Slavic countries. Crimes in Germany on German citizens were not crimes if committed on Jews or conquered populations. Released from normal morality a society of soldiers develop their own. One they would be horrified at in civilian life, yet are compelled by peer pressure and with the tacit support of their commanders.
This happens quickly. I remember when Thatcher launched her Falklands War on Argentina. Within days the media were talking about killing “ Argies” . It’s important to give the enemies a horrible nickname so you don’t have to consider them as humans any longer. Thatcher had no moral problem in sinking a ship ( the Belgrano) with 1000 young conscripts on board, each with a family who would grieve at their death.
In Vietnam the enemy were “ gooks” and so on and the atrocities young law abiding Americans inflicted on a population that was in now way threatening them at home beggars belief when it’s all over and returned to “ peacetime” morality.
I hope a future society will never see other human beings as dehumanised enemies and believe that war can resolve anything. The question was about rape. From a moral standpoint murder was a bigger crime than rape in civilian society, so if you can murder why shouldn’t you rob, loot and rape?
The criminals in my view are that ruling class who decide that a whole country is an enemy, tell people that a different and opposite morality applies and send young ordinary ( mostly) men to kill other ordinary human beings.