How High is the Price of "Diversity"?

“And as horrific as this tragedy was, if our diversity becomes a casualty, I think that’s worse ….” - General Casey

Many people are appalled at this apparent attempt to push diversity on a higher level than human lives, and indeed it is clear that people died perhaps unnecessarily because a 'political correctness' approach prevented the proper actions from taking place.

Question: How many dead people do we need to have to make those deaths more horrific than if "diversity becomes a casualty"?