Racism shouldn't have to be tolerated by anyone, in any way, shape or form, but I do think it is just the minority.
Unfortunately, and I read back to the comments made earlier by Beagle, there is a fine line between racism and controlled immigration. Some people out there believe you to be a racist for believing in controls put in place.
I do agree with him that there needs to be some kind of controlled immigration, for all kind of logistical reasons. Our population has increased by around 8 million in the past 20 years, compared to 2 million in the 20 years prior.
The scenes in the Manchester derby were awful, and was reminiscent of how it was in the 70's.
Fortunately, incidents do tend to be more isolated within our sport, but I have heard it in the past.
Adding to the point, it can be a two way thing too, I know of someone who was working for a company, where the environment became, in his words toxic. Over 50% of the workforce were foreign, and the final straw for him was racial abuse he suffered.