Shades of Evil

Sasha Volokh has taken some heat for denying the uniqueness of the Holocaust as a morally evil event. Despite taking fire from folks like Meryl, he’s sticking to his guns:
Alas, I still don’t buy the moral uniqueness. To repeat my point from below: the Holocaust is evil because killing six million Jews is six million murders, and committing six million murders is highly, highly evil. Really evil. But not more evil than killing six million other innocents. (As I’ve mentioned below, the Holocaust also has lots of characteristics that make it especially grisly, especially memorable, especially important as a cautionary tale, especially relevant in a world of ethnic warfare, etc.; but you can be all those things without having extra evil.)
It’s hard to argue uniqueness of the Holocaust, but I certainly disagree with Sasha that there wasn’t “extra evil” involved in the Nazi plan to exterminate Jews as a people. I can think of two ways in particular:
1) The Nazis planned to not only destroy all individual Jews, but in so doing, destroy Jewish culture and society itself. Had they succeeded, it would have represented a loss to humanity above and beyond that of the individual human lives ended. The complete destruction of Jewish heritage, food, music, art, and custom (or that of any other ethnic or cultural group) is surely a crime in and of itself to be added to the moral evil of the actual murders.
2) From a more scientific viewpoint, if you agree that Jews contstitute an actual ethnic group with particular genetic characteristics (a slippery concept at best, but one I believe can be generally accepted as roughly true), then there is an additional evil involved in trying to wipe them out. It is generally accepted that diversity in humanity’s genetic stock is a good thing in and of itself: more diversity leaves a population better able to resist disease, changes in the environment or other specific challenges. Any reduction in that diversity, therefore — by, say, wiping an entire ethnic group out — is an actual negative to the species as a whole. Hence: extra evil.
PS – Yes, rumors of my demise have been mildly exaggerated. All is well (knock wood), but no, I’m not bringing back the Showcase or catching up on Ecosystem business quite yet…