... think it's more abhorrence than apologist inclinations, LS. Maybe lack of exposure (or at least lack of recognition of exposure, which amounts to the same thing) to the violent side of racist ideology. Lot of people, especially when viscerally exposed to something like this for the first time, are shocked enough by it they can't really wrap their head around it. Especially if they've been around folks that are... well, you probably know the sort -- best people in the world, so long as you're not <insert race>. It's incredibly goddamn jarring the first time you notice the people around you are actually not far off from being murderous assholes. The mind recoils. Doesn't want to accept it, etc., etc. Makes you want to think that the beliefs the people you otherwise respected
couldn't lead to abhorrent acts such as the one in question.
That's... it's not really a bad thing, exactly? Entirely, anyway. People who have that reaction to acts such as these are ones who probably aren't going to perpetrate them, and are fairly likely to spread that kind of reaction to those around them. Naiveté, perhaps, but sorta' a good one, so long as it doesn't blind the person to the existence of what causes acts like these. Which it does have an unfortunate tendency to, as you've kinda' noted, LS, pointing out the similarities to apologist bullshit.
Unfortunately, violence against groups that have been painted as the degenerate Other is entirely too human, too sane, and too normal... there's consequences to professing beliefs