As welcome speeches go...

"You, quite simply, [are] ridiculous. You are either brazenly provocative or astonishingly uneducated. ... I doubt you will have the intellectual courage to answer [our] questions ... I do expect you to exhibit the fanatical mind-set that characterizes so much of what you say and do ... Your preposterous and belligerent statements ... led to your party's defeat in the [last] elections." This was how the president of Columbia University in New York introduced a guest speaker, who was none other than the president of a country "" Mahmoud Ahmadinejad of Iran. Mr Bollinger also called President Ahmadinejad a "petty and cruel dictator". As sheer bad manners and effrontery go, this incident would be hard to beat.

Two things provoked Lee Bollinger, the head of Columbia University, to say such indefensible things to a guest. One, he had been criticised for inviting the Iranian president to the campus, with the objectors focusing on two positions that Mr Ahmadinejad has taken, that the Holocaust never happened, and that Israel ought to be wiped off the map. But the chances are that, had it not been for the second reason, namely, that it was not Mr Bollinger who had invited Mr Ahmadinejad, but the dean of international studies who had done so, he may have felt impelled to behave with greater decorum. It did not help, though, that Mr Bollinger was cheered by the assembled audience, including faculty and students of the university, when he made his disgraceful and outrageous comments. Several contrite American columnists and editorial writers have sought to explain it away by saying that Mr Bollinger felt the need "to show the media, alumni, concerned Jewish organizations and a raft of bellicose neo-conservative pundits that he was no terrorist-loving appeaser of Holocaust deniers", but they and others should know that that is no excuse.

The Iranian president's reply was the perfect contrapunt. He was courteous and patient. He reminded his host that it was a discourtesy to the assembled gathering to make up their minds for them about what their guest would say before the guest had spoken. He was questioned with a great deal of hostility but never lost his cool. Some of what he said might have sounded bizarre to the audience, but it is perhaps worth noting that on the Holocaust and Israel, he answered questions with counter-questions that are also difficult to answer. In any case, never once did he descend to the depths that his host had done.

This incident points to an American peculiarity: the constant need to have someone to demonise and to hate. Anyone even remotely familiar with American history knows that, whether it was burning witches in the 18th century or decimating native Americans in the 19th or lynching blacks in the 19th and 20th centuries or going after the Communists in the 20th (remember 'Better dead than Red'?) or turning former friend Saddam Hussein into Foe No. 1 in the 21st ... America seemingly needs a hate object; France became one in 2003 (remember "Freedom Fries") until the Iraq war went all wrong, Iran has been one ever since the Shah was overthrown nearly three decades ago, China's currency policy is responsible for America's economic troubles, North Korea is part of the "axis of evil"...

Many will argue that America is not an exception in this regard, and they would be right but the uncomfortable fact is that America does more intensely and more often what others also indulge in "" focus on an external enemy in order to bind together the domestic constituency. Whatever the case, it is something for Americans to ponder over when a man who everyone assumes is educated, cultured and civilised behaves like an abusive fishwife when welcoming a head of state.