Not sorry as in apology ("apology" is admission of culpability for wrongdoing), sorry as in, you know, sorrow. Regret. Actually I'm not sorry at all, thinking of it!
But you know what, I've been putting some thought into the idea that racism makes white people look bad. Or that accusations of racism against white people make white people look bad. Or that a person might feel accused by race proxy, when one of their race is accused. I'm trying to figure out why I have no sense of this myself. I THINK I HAVE IT!
I think rampant racism and rampant accusations of racism only make white people feel they look bad when they themselves aren't, for whatever reason, part of the fight. I mean, somebody wants to accuse me of racism, that's cool - first thing I KNOW is THEY are PART OF THE FIGHT!
And it's MY side bastard and WELCOME TO IT. Now maybe somehow I made myself look like a fool or an ass, or even a racist. I kind of want to know more on that. I'm kind of GLAD THEY BROUGHT IT UP. We can straighten out our accusations quite vigorously, and I'm confident at least both of us will end up on the side that believes in and advocates for human rights for all humans, and opposes strongly the ignorance and ill-effects of race-based bigotry. The part where I learn what I did wrong, if any, or what I did to give the appearance - that part is very much needed and welcomed.
How can I be insulted by a person who hates racial bigotry enough to call someone on it?
Whereas I can see that if I were apathetic or complacent or barely cared at all, or felt it was "not my problem" - well, I'm sure that if I believed humanity is not my problem, then there could possibly be some buried discomfort with that. And I could easily see how it would trigger that discomfort when the topic comes up, or when accusation's all around. It'd be sure to make me feel guilty. Not guilty of being a racist, but guilty of doing absolutely nothing meaningful - not even LIP SERVICE - to be part of the fight.
This is why racists, too, I suspect don't feel much of this "accused by proxy" thing. They are PART OF THE FIGHT. There's no reason for them to duck or deny, or feel buried guilt for doing nothing.
As the previous paragraph trenchantly points out, being "part of the fight" is not necessarily admirable in itself. It matters a deal which fight, and which part of it you take.