I take this to be generally true, but I think there is one distinction to be made: most people do not assume that white crime, black crime, or Muslim crime is reflective of the entire ethnic group. What we are talking about here is a group of people coming into the country new, who are seen to be, erroneously or not, as high offenders. Many years ago, a council estate was built in my home town and it was populated with people brought in from high crime areas of Manchester, and once they arrived crime went up. Is it prejudice to show concern about that population being there? I think not. It certainly didn’t mean that we all felt people from Manchester were criminals.
For me, the trick here is not to attack these people for being racist (either they are and don’t care, or aren’t and find it offensive or even just plain baffling that you would call them that in the first place), surely it’s better to unite people by focusing on what they have in common which is economics, because actually, it’s through economics that both groups are made to suffer. (And I’m certainly not advocating turning a blind eye to racism).
I get your point about the silence of white working classes when black or Hispanic communities were / are under threat, that is indeed an hypocrisy, but not an unsurprising one since most people don’t get upset until something touches them personally, but it could also be an American thing, because working class communities in Britain have a strong tradition of fighting racism and standing up to bullies, such as when the East End of London saw off Oswald Mosely and his black shirts. I don’t even think the rise of UKIP here in Britain has much to do with race really, but disaffection, and a feeling that they’ve been deserted by parties which do have strong anti-racist traditions. If there is one thing I despite Tony Blair for (ok forgetting the war) is what he did to erode the concept of class. Now its all about fucking race instead. But perhaps we are taking at cross purposes because things might be very different in the States, and my defence of what Cristo and Drayton have said, may only apply to my own country, although i still disagree with your textbook definition of racism.
EDIT - I do actually agree with your definition just with caveats.