KEY POINTS:
The revelation that Adolf Hitler's record collection included works by Jewish musicians whom his regime branded subhuman is significant, not for the discrepancy between the public figure and the private individual per se, but because it was assumed that if there was one historical monster who believed unswervingly in his credo, it was the monster who insisted in Mein Kampf that Jewish art "never existed".
If history teaches us anything it's that rulers operate on the basis of do as I say, not as I do. The more authoritarian the ruler, the greater the divergence; the more strident the morality, the dirtier the secret; the more austere the regimen, the more piggish the clandestine self-indulgence. And the more black-and-white the ideology, the more breath-taking the hypocrisy.
When it comes to breathtaking hypocrisy, organised religion is the mother lode. Since well before Jesus chased money-lenders out of the temple, religious leaders have been preaching one thing and practising the opposite.
For centuries the church's high command - popes, cardinals, bishops - preached the virtues of self-denial and oversaw the scourging and burning of backsliders and heretics while living the high life with their courtesans and catamites in the privacy of their gilded palaces.
Then there are the devoutly Muslim sheiks and princes who behead adulterers and flog beer-drinkers before flitting off to Monte Carlo in their private jets for alcohol-fuelled binges with the cream of the call-girl crop, not to mention those nauseating evangelists who in parts of the US have transformed Christianity into televised flimflam.
Jimmy Swaggart, who specialised in exposing the infidelities of rival ministers - "Cancers on the body of Christ" he charmingly called them - while availing himself of the services of prostitutes, is an appropriate poster boy for this gallery of sleazebags and bigots.
Meanwhile, the underground army of predatory priests have reduced the Christian motif of the shepherd and his flock to the level of a dirty joke.
Ever since Stalin filled in time between purging old comrades and exterminating peasants by watching western movies, communist leaders have flouted Marxist principles, notably from each according to his ability to each according to his needs.
Perhaps the most staggering example of a communist leader behaving like a plutocrat came from the Romanian dictator Nicolae Ceausescu, who laid waste to Bucharest's old quarter, including 7000 homes, to build a palace of unimaginable grandiosity. The third largest building in the world, it has an underground car park that could accommodate Buckingham Palace.
This lunatic tradition is now carried on by North Korea's Kim Jong Il, a fan of Bond movies, whose wretched, malnourished people would be interested to know that their leader is Hennessy Cognac's single biggest customer.
The hypocrisies of political leaders in Western democracies, who have less scope for looting public coffers or annihilating opponents and undesirables, generally centre on sex.
British Prime Minister John Major's 1993 announcement of a Back to Basics policy aimed at restoring public probity and old-fashioned moral values triggered an exodus of Tory skeletons from closets all over Westminster.
This cavalcade of sleaze, featuring a cast of pimps, prostitutes, love children, and rent boys, generated increasing mirth which reached hysterical levels following the accidental death by auto-erotic asphyxiation of high-flying MP Stephen Milligan, who died not with his boots on but wearing stockings and suspenders.
The beat goes on. Mark Foley, a six-term Republican Congressman from Florida, who championed the protection of children from sexual predators, resigned after it was revealed that he had bombarded teenage congressional pages with text and email messages which were salacious to the point of amounting to phone sex.
Only last month an Italian MP (Catholic, married, wife expecting their fourth child, belonging to a party that espouses family values - the usual suspect in other words), who had campaigned for all MPs to be drug-tested, was discovered in a hotel room with a prostitute who had overdosed on cocaine.
Asked if he'd paid her for sex, he came up with a reply which surely now features in the Italian equivalent of the Tui billboard campaign: "Not exactly; I spontaneously gave her a present." As you do.
No summary of this dismal phenomenon would be complete without a dishonourable mention for those African leaders who lay guilt-trips on the West then divert aid monies into their Swiss bank accounts while their people starve or perish through lack of basic medicines. Would there be a more stomach-turning read in all of literature than The Collected Speeches of Robert Mugabe?
And as in most areas of human endeavour and egregiousness, New Zealand can put forward a candidate to rival the best or worst: step forward Graham Capill, former Christian Heritage Party leader and father of 10, now serving a nine-year jail sentence for sexually abusing young girls.
