Things like that illustrate that political correctness is like a cultural equivalent to what on the individual level is called insanity: it's a belief structure that reinforces thinking which is out of touch with reality to the point where calling it psychotic is probably not an exaggeration. The survival instinct is one of the most basic to human nature; political correctness subordinates even that to its need to repress patently-obvious facts which conflict with its defense mechanisms.
Psychotic indeed.
As Moral Hazard commented on another thread, recently DNA sequencing has shown that women are more different from men genetically than either are to their chimpanzee counterparts. But mentioning that this might relate to the differences in our behavior almost got Summers fired.
I think Ward Churchill may find someday that his 15 minutes of fame was more like people slowing down to take in the view of a serious car accident than anything else.