Discarding conventional diplomatic channels - opting instead for a global phone-in on the music station MTV on Thursday night - Mr Powell urged young people to "forget about conservative ideas [and] protect yourself" when it came to Aids prevention, a message that contradicts Mr Bush's view that abstinence, not contraception, is the answer.

Asked by a Catholic woman from Milan what he made of the Pope's opposition to condoms, Mr Powell smiled and directed a few respectful words at the Vatican before opening a new front against his administration's stated position on sex education.

"It is important that the whole international community come together, speak candidly about it, forget about taboos, forget about conservative ideas with respect to what you should tell young people about. It's the lives of young people that are put at risk by unsafe sex," he said. "And, therefore, protect yourself."

Some American conservatives argue that condoms give a false sense of security.

"He's the secretary of state, not the secretary of sex education," the former presidential candidate Gary Bauer, who is president of the pressure group American Values, told the Guardian yesterday. "Condoms do not protect against some of the worst viruses that have been linked to cervical cancer, and nor are 14 or 15-year-olds likely to use condoms effectively. The secretary should stick to diplomacy."

The White House launched a swift damage-limitation exercise, with Mr Bush's spokesman, Ari Fleischer, saying Mr Powell was only addressing "people who are sexually active" and therefore not contradicting the abstinence line.

During a program lasting more than an hour, Mr Powell - standing on a picture of the globe and wearing, unlike his questioners, a dark suit and tie - fielded often acerbic questions on race, terrorism, the Middle East and Aids medication from viewers in Washington DC, London, Cairo, New Delhi, Milan, and Sao Paulo.

His most personal response was to a Washington student who asked him why he once said: "I ain't that black."

"Because I am not that black as a physical matter," Mr Powell replied. "I'm as black as anybody whose skin could be 20 shades darker. I consider myself an African-American, a black man, proud of it, proud to stand on the shoulders of those who went before me."

Being raised in a multi-ethnic neighborhood and trained in the military, he said, meant: "I'm probably more acceptable to the white power structure that I was dealing with when I was coming up... [but] I've been thrown out of places because I was just black enough not to be served."

A 19-year-old Norwegian asked from the London studio what it felt like to represent "a country commonly perceived as the Satan of contemporary politics". The secretary of state retorted: "I would say we are the 'Great Protector'."

When an Afghan man asked him why the US had not confronted the Taliban before September 11, he said: "We were slow off the mark."

Mr Powell's Republican critics can console themselves that he avoided the embarrassment of Bill Clinton on MTV in 1994, who was asked if he wore boxers or briefs. "Mostly briefs," a queasy-looking Clinton was forced to reply.

© Guardian Newspapers Limited 2002

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