Deniers attempt to morally justify most Nazi acts that they do not deny. Siegert and Rudolf have defended reprisals; Hargis has defended the shooting of Jewish children; and both Berg and Porter have defended deportations to 'internment' camps. These defenses only make sense if we assume a threshold for the definition of genocide that is far higher than that used by the UN. Deniers state there was no genocide of the Jews; thus deportations, reprisal killings, and even executions of children, are not genocide.
Why do deniers insist on this high threshold for genocide and is it logically sustainable? The two parts of this question are interconnected. Deniers insist on the high threshold partially because they wish to impose a fallacy of personal incredulity on the events they deny. Their argument, in a nutshell, is that gassing claims and atrocity 'propaganda' require the Germans to have exhibited a degree of personal cruelty and malevolence that is psychopathic and demonic. The Holocaust is thus, in their view, a form of mystical demonology.
This position is only sustainable, however, by ignoring the malice present in the Nazi acts that deniers are happy to defend. Was it cruel to rob Jews of their property? Hargis says 'no'. Was it cruel to break up families and separate the sexes? Apparently not. Most importantly of all, the threshold ignores simple maths. A ratio of killing that equates a hundred Jews to one dead German - which Siegert and Rudolf defend - is a more cruel ratio than if a decision had been made to kill between five and six million Jews in reprisal for the deaths of over two million Germans in World War I. The acceptance by deniers of the fact that Germany employed a 100:1 killing ratio should therefore destroy any incredulity defense when faced with evidence that Hitler authorized a genocide, and a vengeful SS carried out that genocide, in fulfillment of a desire to exterminate a 'race' that had 'stabbed Germany in the back.'
However, contra deniers and contra Goldhagen, to accept that these acts were cruel, and that the perpetrators were therefore perfectly capable of killing six million Jews, is not to engage in demonology. When an ideology of vengeance, which may be held by just a few individuals, is spread through a state bureaucracy with a culture of violence, the state can commit acts of cruelty without most of its members being sadists or psychopaths or 'exterminationist antisemites.' Moreover, the genocidal nature of Nazi acts does not preclude comparisons with similar acts by other states. Anti-deniers should not, in my view, argue that the Nazi state was 'uniquely' genocidal whilst ignoring genocidal acts committed by the allies, but nor should they ignore the fact that Nazi genocide had racial underpinnings that made it more likely to escalate into an attempt to kill every Jew in Europe, thereby exceeding all other genocidal acts in their attempted scope and comprehensiveness.
Instead, anti-deniers need to be more mindful of a high denier threshold for genocide when debating such issues as the gas chambers at the death camps. It would be a dangerous error to create the impression that anti-deniers were agreeing with deniers that the crucial crossing of the threshold of genocide did not occur until the Nazis began to gas children at Chelmno, or until the Einsatzgruppen began to shoot women and children in the USSR. The threshold was crossed far earlier than that, in acts that deniers have never claimed did not take place. The full moral meaning of that fact is a fundamental truth that deniers cannot face. Their shifting of moral boundaries is therefore the ultimate 'denial within denial'.