The secret of tolerance:
of people can get under our skin sometimes and it's all natural. But along the lines of what Herra Tohtori posted tolerance can be achieved. The secret is sort of a revelation - we are no better than anybody else in this world. Hard to believe but we aren't. The differences I honestly believe lie in the decisions we make as individuals.
Once we truly see/feel that we are no better are attitude changes towards everybody. Of course real life can blind us from time to time and this is easier to say when our stress levels are down. 
But I honestly believe it can be done.
I don't think that's true at all. Tell anyone to emulate any one of a dozen famous people who have revolutionized the course of history and they'll probably say it's not a bad idea, although they might disagree with you on the exact way you might go about doing that. Tell anyone to emulate any one of a dozen famous serial rapists or child molestors and I doubt you'll get anywhere near as positive of an answer.
So I don't think tolerance is 'everybody is OK'. There are people who are intolerant of other people who have to be...well, I don't know what the word to use is, but you get the picture. You cannot be tolerant of everybody because sometimes people's wants and even needs conflict. Sometimes two people have a deep-rooted interest in something, neither can be satisfied without dissatisfying the other, and no compromise is possible. Sometimes somebody is simply intolerant of others and the only way to solve that problem is to make them stop being intolerant of others by being intolerant to them.
And it's that particular factor that trips people up all the time. People will assume that their experiences are valid, and that the things that do things for them will do the same thing for others, and that the things that other people want are similar to the same things that they want. People assume that they're more enlightened than somebody else at the same time that their target is thinking the same thing about them.
Doesn't mean that everybody's answer is as valid as everybody else's, or that everybody is write or wrong. It's none of the above and it's much more complex than any of these ideals would have you believe. Somebody can be known for being utterly intolerant, but cause a backlash of tolerance as other people react to that intolerance. Yet that first person may not even be more intolerant than many other people that nobody cares about. Yet it's the way that they're intolerant, and the fact that other people (in their intolerance) label them as intolerant that causes such a wave of goodwill and positive effects.
That's probably as confusing as hell.

I don't have the historical context to make this as support to that statement, but I'll put it forward as what I suspect is a real-life example: Malcolm X. Pretty damn controversial figure. Yet at the same time, he helped to highly publicize racial inequalities and I would guess that, as a consequence of his speeches, more was done to achieve racial equality than if there had just been a general apathy in place of the polarization from his speeches. People, in general, react more to an obvious problem than to a quiet problem. By causing so much controversy and getting himself labeled a "menace to society" he made racial inequality a big problem.
But of course if people were tolerant to that kind of behavior, it wouldn't be a big deal.
So...I believe that tolerance is a good thing, but also that sometimes intolerance is more tolerant than tolerance, and that true wisdom is knowing when to be tolerant and intolerant (among other things).