I really like the "tolerance is not a moral precept, it's a peace treaty" reading of tolerance:

Tolerance is not a moral absolute; it is a peace treaty. Tolerance is a social norm because it allows different people to live side-by-side without being at each other’s throats. It means that we accept that people may be different from us, in their customs, in their behavior, in their dress, in their sex lives, and that if this doesn’t directly affect our lives, it is none of our business. But the model of a peace treaty differs from the model of a moral precept in one simple way: the protection of a peace treaty only extends to those willing to abide by its terms. It is an agreement to live in peace, not an agreement to be peaceful no matter the conduct of others. A peace treaty is not a suicide pact.