The testimony from Commanders, other officers and enlisted men in the German forces serving in north Italy in 1944 reflects the fear and hatred that regular soldiers have for irregulars or guerilla forces that attack them then slip away and hide amongst the civilian population. This is intensified in circumstances where they are retreating from enemy forces through territory where a civil war is taking place between Italian partisans and fascists and where the German army has poor lines of support and communication. It also reflects the contempt, possibly even racism based on Nazi ideology, which many held for former allies who have now capitulated and joined the enemy and may also have led some troops, to de-humanize the Italian civilian population. We have seen similar tendencies in other more recent wars, including Vietnam, Iraq and Afghanistan.
But, at the same time, an explanation of military behaviour at a particular moment in time is never a justification of it.
Although it is true that the International Laws of War prior to 1945 had mainly emphasised rules for the treatment of wounded combatants and prisoners of war and it was necessary after World War II to extend the Geneva Conventions to protect civilians more effectively it is also clear that the existing Laws of War condemned the torture and massacre of civilians in times of war. It is also clear that the German Military Code of 1940 stated that officers and enlisted soldiers would be held responsible for such atrocities.
The only real issue here is whether the evidence about the massacre at Monte Sole demonstrates war crimes by particular SS reconnaissance units or demonstrates a more systematic policy laid down by the German High Command which would be evidence of crimes against humanity.