Aaronovitch, Wheen and Julius all warn against the dangers of shallow tolerance. Wheen puts the case for the prosecution best when he writes: "Irrationality is both cumulative and contagious. You start by reading your horoscope in the newspaper; then you dabble in chakra balancing or feng shui, saying that it is important to keep an open mind; after a while your mind is so open that your brains fall out, and you read the Protocols of the Elders of Zion without noticing anything amiss." Permissiveness and the needs of commerce fit together well. Respectable publishers no longer feel ashamed about printing profitable tosh they would have been too embarrassed to have on their lists a generation before. David Aaronovitch sees the same collapse of standards in the supposedly regulated television industry, where commissioning editors want to combine novelty with shock value and feel no compunction about revealing "the hidden truth" even when they know that the "truth" they reveal is fantasy. The overworked and underpaid assistant producers who labour beneath them on documentaries, daytime chat shows and around-the-clock news are left in no doubt that they must find suitably controversial material to hold the attention of the audience. They produce a version of fusion paranoia, not because they are themselves paranoid but because there is money in the madness. The triviality of a time that places a virtue on abstaining from judgment allows them to escape the censure they deserve. Once honest rogues shrugged their shoulders and admitted that they were just turning a profit by giving the public whatever nonsense it wanted. Their pious successors get away with covering up the chase for ratings and revenues with self-justificatory cries of "we need to hear the other side" and "we're just asking difficult questions", and fail to realise that they are breaking down old prohibitions while they are about it. 

In his examination of how the crude forgery of the Protocols came to inspire the murder of millions, Norman Cohn was being properly sardonic when he wrote of "usually sane and responsible people". Sensible societies throw cordons sanitaires around dangerous ideas, because they know that "usually sane and responsible people" cannot be counted on to see their flaws. After the Second World War, the ideas of Nazism became taboo in Europe — get too close to them and you were denounced. To my exasperation, my comrades on the Left have worked hardest to pull down the barriers by providing platforms for Islamist radicals they would denounce as "fascists" if they had white skins. Predictably, the far-right British National Party has broken out of its cage. It can now announce that its version of neo-fascism is not as extreme as ideas tolerated without objection in polite society. As culpable as the pseudo-Left are all the clueless journalists and civil servants in the mainstream who think it is virtuous rather than cowardly to be non-judgmental about ideas that demand to be judged.