I don't think it affects your larger point, but "Hitler's Willing Executioners" is, at best, controversial. (Personally I think it's mostly crap.) Check out "A Nation on Trial" by Finkelstein and Birn in English or "Ein Volk von Moerdern" in German while Goldhagen is still fresh in your mind.
I don't speak German, but I am aware of the work by Norman Finkelstein and Ruth Birn, and of the controversies surrounding Goldhagen's book. Some of the latter stem, I believe, from a misreading or over-interpretation of Goldhagen's work, which states repeatedly that is dealing with one narrow, specific aspect of the Nazi phenomenon and the Holocaust: namely, the actions of the people who actually inflicted the torments and perpetrated the killings (and those who administratively facilitated these actions). It deals with the fact that almost all of the perpetrators acted of their own free will -- very often with enthusiasm and initiative, above and beyond the call of duty -- even when, in many if not most cases, they could have refused such duties without penalty.
Goldhagen also deals with the anti-Semitism that soaked German society, the obsessive idea that there was a "Jewish problem" that needed to be solved in one way or another, and the overwhelming acceptance of the notion that Jews should be segregated and removed, in one fashion or another, from German society (which Finkelstein also acknowledges). Goldhagen states repeatedly that this pervasive anti-Semitism was not the sole and inevitable cause of the Holocaust; but he does assert that it was an indispensable element in the development of the "Final Solution" of mass deportation, mass suffering, and mass murder. Without this baseline, without the pervasive belief that Jews were somehow lesser beings, were destructive, poisonous "Others" whose very presence caused terrible harm to the German nation, then the Nazis would not have been able to move from the Nuremberg Laws (which, as Finkelstein notes, were met with overwhelming public approval) to the death-camps.
Goldhagen also makes clear that even with the pervasive anti-Semitism -- "eliminationist" in that it wished and approved the removal of Jews from the life of German society -- the mass killing and worst depredations would not have occurred if not for the war, and the savagery it unleashed. (Unleashed on all sides; the indiscriminate Allied bombing of German cities and the resulting mass civilian deaths were repeatedly cited by death-squad leaders and other officials as "justification" for their own killing of unarmed, non-combatant civilians, especially Jews, who, in the widely-accepted Nazi mythology, had somehow "caused" the war.)
The heart of Goldhagen's book are the hundreds of pages of descriptions of the activities of the perpetrators, told often in their own words, and the direct evidence of their positive attitude toward their activities -- activities which were more widely known in society than is generally assumed. As he notes, many of these testimonies have been ignored or under-utilized in examinations of the Holocaust, and thus the focus of his book is filling out this neglected niche in the vast field of Nazi-era studies. Goldhagen also makes clear, repeatedly, that these events had nothing to do with any racial, biological, national, spiritual or any other inherent quality in the German people; they arose out of a certain specific set of historical conditions.
Nor does he say, anywhere, either directly or by implication, that "the Germans are a species apart with their pathological anti-Semitism, [which] absolves them of all normal standards of moral culpability," as Birn alleges. She accuses of Goldhagen of having a "sugar-coated version of the Holocaust" (!), "which eliminates the need for people to constantly think about the ethical choices of right and wrong. " This conclusion simply cannot be supported by a reading of the book. Goldhagen repeatedly and explicitly rejects this thesis, and instead points out, over and over and over again, that the atrocities were carried out by individual moral agents, who were responsible for their actions, and who had to make constant ethical choices of right and wrong every single day -- especially given the fact, as Goldhagen demonstrates, that many if not most of the perpetrators could have stopped taking part in the atrocities at any time. Indeed, the moral culpability of individuals is in many ways the whole point of the book.
What Goldhagen is trying to do is to understand why so many Germans in that era made the choices they did to take part in such a monstrous activity. To try to understand a motive is not the same as explaining it away or absolving the perpetrator of his or her moral culpability. The latter is the argument made by apologists for the Terror War -- that you are "pro-terrorist" or "blaming the victim" or "absolving the terrorist" if you try to understand what motivates someone to take such an extreme action. It is also the argument made by apologists for Israel's manifold depredations against the Palestinians. And Finkelstein and Birn -- especially Finkelstein -- obviously do not fall into the camp of such apologists. Yet they are using a version of that discreditable argument in the case of Goldhagen's book.
Again, this is not to endorse every single conclusion that Goldhagen draws from the evidence and the testimonies he examines. Nor do I have the slightest desire to wade into what is in many ways an academic cat-fight, and one which has more to do with present-day politics than historical truth. (On the political side, I am much in sympathy with Finkelstein, who has been subjected to censorship, prejudice and banishment (from Israel) for his own scholarship; including his critiques of Goldhagen.) I don't know what Goldhagen's politics are. I don't doubt that the book has been put to partisan use, or that it contains conclusions and interpretations open to dispute or refutation. What work of history doesn't? But I am not an academic, or an intellectual, or an ideologue. What I am interested in are the historical facts that he presents, and what they say about human nature, and the patterns and dynamics of human behavior, especially in the context of large-scale actions initiated by a powerful state.