The entry of the U.S. into the War is also crucial to the time-frame proposed by Christian Gerlach, who argued in his 1997 thesis,[122] that the Final Solution decision was announced on 12 December 1941, when Hitler addressed a meeting of the Nazi Party (the Reichsleiter) and of regional party leaders (the Gauleiter).[123][a] The day after Hitler's speech, on 13 December 1941 Joseph Goebbels wrote in his diary:[125]
Similarly, in Ordinary Men (1992), Christopher Browning examined the deeds of German Reserve Police Battalion 101 of the Ordnungspolizei ("order police"), used to commit massacres and round-ups of Jews, as well as mass deportations to the death camps. The members of the battalion were middle-aged men of working-class background from Hamburg, who were too old for regular military duty. They were given no special training. During the murder of 1,500 Jews from Józefów in Poland, their commander allowed them to opt out of direct participation. Fewer than 12 men out of a battalion of 500 did so. Influenced by the Milgram experiment on obedience, Browning argued that the men killed out of peer pressure, not bloodlust.[471]
In several instances, Jews took matters into their own hands and violently resisted the Nazis. The most notable was the 28-day battle waged inside the Warsaw Ghetto. There, a group of 750 Jews armed with smuggled-in weapons battled over 2000 SS soldiers armed with small tanks, artillery and flame throwers. Upon encountering stiff resistance from the Jews, the Nazis decided to burn down the entire ghetto.
“Could the tunnel ever be excavated?” I asked Freund. He told me that the Vilna Gaon Museum, although already planning renovations at the site, was still deciding how to proceed, but that he has counseled against full excavation: He’d invited an architect and tunnel expert named Ken Bensimon to analyze the site, and Bensimon had concluded that even if a rabbi signed off on a dig—a necessity, given the proximity to what amounts to mass graves—the integrity of the passageway would be unlikely to hold.
The Nazis brought their own strain of radical ruthlessness to these ideas. They glorified war and saw the uncompromising struggle for survival between nations and races as the engine of human progress. They rejected morality as a Jewish idea, which had corrupted and weakened the German people. They maintained that a great nation such as Germany had the right and duty to build an empire based on the subjugation of 'inferior races'. They looked eastwards to Poland and Russia (where, as it happened, the great majority of European Jews lived) for the territorial expansion of their 'living space' (Lebensraum).
Three defendants were acquitted. However, many of the Nazis who perpetrated the Holocaust were never tried or punished, including Hitler who had committed suicide. Since then, the international community has continued and improved accountability through forums such as the International Criminal Court, and the International Criminal Tribunal for Rwanda.
Amit withstood pressure from many members of his staff who were Holocaust survivors or relatives of victims. But others thought he was right. Rafi Eitan, an Israel-born Mossad operative who led the team that caught Eichmann, told me: “Because of the need for foreign-language speakers, many of the Mossad’s recruits were from Europe, and therefore had gone through the Holocaust or lost their families in it. One can definitely understand their need for vengeance. However, there was huge pressure to deal with current requirements, and with the resources being as meager as they were, in no way would it have been right to give the Nazi matter priority.”
Although Dr. Josef Mengele did not join the staff at Birkenau until May 1943, survivors testified during the Allied war crimes trials that he did selections in 1942. Besides the initial selection when the transport trains arrived at Birkenau, there were later selections of the women in the camp. Dr. Mengele was the chief doctor for the women's barracks, and he would periodically show up to select women for work or the gas chamber. One of the women who survived one of these selections was Sophia Litwinska, a Polish Jewess who was married to an Aryan man.

In addition to active help, many clergymen also protested the mistreatment and deportations of Jews as violations of divine and human laws. The Catholic pastor of St. Hedwig’s Cathedral in Berlin, Bernard Lichtenburg, prayed publicly for the Jews until his arrest and death on the way to Dachau. The rescue work of priests of all Christian denominations is well-documented in postwar literature.
Mengele's work also involved carrying out selections, a task that he chose to perform even when he was not assigned to do so, in the hope of finding subjects for his experiments,[33] with a particular interest in locating sets of twins.[34] In contrast to most of the other SS doctors, who viewed selections as one of their most stressful and unpleasant duties, he undertook the task with a flamboyant air, often smiling or whistling a tune.[35][31] He was also one of the SS doctors responsible for supervising the administration of Zyklon B, the cyanide-based pesticide that was used for the mass killings in the Birkenau gas chambers. He served in this capacity at the gas chambers located in crematoria IV and V.[36]