When I was 12 years old, a Native girl told me I was 'too white to be a person'. Recently, I read someone mocking a white woman for being offended by the statement that 'white chicks' were untrustworthy. Malcolm X called us 'white devils'.
The same people who vehemently oppose similar statements towards other races are often willing to tolerate it towards white people. Racist jokes against white people are 'humorous' while against any other race they are intolerable.
This happens with other forms of discrimination. I've heard many women make sexist comments or jokes about men that would not be tolerated if they were made about women. Saying women aren't as smart as men is sexist, right? Then why do so many women seem fine with saying the opposite (for example, one joke states that God offered two gifts to the first man and women, saying they could chose to get either brains, or the ability to pee standing up)?
Regarding autistic rights, I see this so often in the suggestion that NTs are inherently stupid, manipulative, immoral liars, or that they are boring. Discrimination is treated as a distinctly NT behaviour, as are bullying and many other things. The same people who make claims like that are generally the autistics most prone to doing the exact things they accuse NTs of - the ones who are most prejudiced and bullying.
Now, some people claim reverse discrimination simply because they are losing the privileges they are unfairly given. This is certainly true. There are also some people who claim more traditional discrimination when they don't get what they want for very different reasons, as Joel Smith described recently. I remember someone on one listserv complaining that he was being denied some legal-type post because of his Asperger Syndrome diagnosis, but it transpired that he was in fact denied the job because he was a convicted sex offender. Now, personally, I think it's just fine to deny a legal job to someone who has shown a substantial disrespect for the law, in doing something as serious as what he'd done (I believe it was some kind of sexual assault).
But reverse discrimination does happen, and it hurts. Up until recently, I absolutely hated my skin color. White is beautiful, just as black is, but I couldn't see it. I felt personally responsible for all the wrongs that white people have done over history to other races. What I'd read never gave a hint that it wasn't just us who were racist, never discussed racism from other races. The Uyghur people, in western China, are discriminated against by the Mandarin majority. That's only one of many examples, which show that white people aren't the only racists. But non-white racists are invisible. As are many anti-male sexists, and anti-normal disabled people.
I used to think that victims of bullying were 'good guys', the bullies and bystanders were 'bad guys'. But being victimized does not make you morally superior. It says absolutely nothing about your morals. It only indicates anything about the ones who hurt you. And you should not judge an entire category of people based on the actions of some of them. It's wrong when it's done by those in power, and it's wrong when it's done back at them by the oppressed people. Revenge will not make it better, it only perpetuates the hurt.