The way they get around that caveat is by the mantra "We tolerate everything but intolerance" which is the result of mining this insipid tautology from leftist philosopher Karl Popper: "
"Unlimited tolerance must lead to the disappearance of tolerance. If we extend unlimited tolerance even to those who are intolerant, if we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them. [...] We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant.”