[pixelmonkey]

Your comment is precisely the paradox, though. "You can absolutely tolerant them until they get the majority of votes." First of all, it's not every society where a "majority of votes" grants political power. In Greece, the White Supremacist group (Golden Dawn) holds parliament seats even though they are a small (but vocal and politically active) minority. White supremacists now influence policy in Greece despite being a minority.

In the Middle East, this kind of outsize influence might be even worse. I am no expert on Middle East politics, but I think it's fair to say that the most intolerant factions have striven to gain the most political power, in spite of the political leanings of the mass populations over which they rule.

One issue with intolerant groups is that they tend toward violence and oppression of opposing speech. The tolerant and pacifist among us can allow them to gain enough minority power to effect a political coup, which can result in a societal coup, since having political control can grant you some degree of societal control.

In such a society, espousing tolerance might carry with it the risk of violent retribution (since tolerance is viewed by the "in" group as heresy/dissent). This will cause the intolerance to spread, even if seemingly against the will of more tolerant citizens. In this way, certain ideologies can have a "toxic" societal effect. You don't need to look far in modern history to find examples. And, that's the paradox.