On What to Do When You Fight in a War in Which 60 Million People Perish, in Which Your Side Engages in Some of the Most Noxious War Crimes in Human History (Torture, the Targeting of Civilians, Ethnic Cleansing, the Wholesale Raping of German Women, the Katyn Forest Massacre, Operation Keelhaul, etc.) and in Which the Aim of the War (in this Instance, Liberating Poland) Not Only Wasn't Met but One in Which the World Was Actually Worse Off Afterwards

In the words of Super Snooper, "Ah, it's elementary, Blab." a) You lie through your teeth and b) you demonize the other side to an almost absurd level. General Montgomery was one of the few who saw through the BS early on and perhaps he stated it best when he said that Nuremberg essentially made it a crime to lose a war, and a high crime at that.