Except for the fact that this argument makes perfect sense in a discussion about Jews and Nazis. It takes the form of Reductio ad Absurdum in that I demonstrate that the views held by OP are similarly untenable by pointing out the historical significance of his position. I have not assaulted his character via Ad Hominem, which is required in the so-called "Reductio ad Hitlerum"; I have merely pointed out the fallacy in arguing that because the Nazis assumed Jews were a race, that Jews must in fact be a race.

And I don't even need that argument to make my point. In most parts of the German occupation of foreign nations (and in their home country), the Nazis used membership lists of synagogues and absence of baptism certificates to prove Judaism, not any sort of common genetic ancestry. The morphological methods emerged in Eastern Europe, but were not significantly used.

If you have a single leg to stand on besides your own childish incredulity, please provide it.