In the summer of 1940, Reinhard Heydrich, the chief of the Reich Main Security Office (including the Gestapo), noted that: "...compared to the crimes, robberies and excesses committed by the army of the Wehrmacht, the SS and the police don't look all that bad". Even when the German Army was not involved in war crimes, all of the top military leaders were aware of what was happening in Poland. None objected on moral principles; the few who did object did so due to concerns about discipline. Moreover, the general who objected the loudest to war crimes in Poland, General Johannes Blaskowitz, was opposed to the Army committing war crimes with the SS, not the idea of atrocities against Poland. The Israeli historian Omer Bartov wrote that Blaskowitz was actually "legitimizing murder" by expressing approval of SS massacres while demanding that the Army be kept out of the massacres as damaging to discipline. Bartov wrote that once officers and troops saw that murder was "legitimate" in Poland, the effect was that the Army tended to copy the SS.