News flash: an interesting political speech was made at the weekend. Deflating second flash: it was made by Paddy Ashdown. This is deflating not because Ashdown is a secondary figure at Westminster, though he is, but because he has made some interesting speeches before; indeed, being "interesting" is one of the Liberal Democrat leader's more dangerous hobbies.

He is treated atrociously by the political elite - mocked, sneered at, never taken seriously. The other parties regard him as "pious", by which they mean outspoken, disdainful and insufficiently respectful of their authority.

And indeed, he is in many ways more like a political commentator than a politician except that he, unlike us, goes round the country talking to people. He saturates himself in the anti-Westminster atmosphere. His wife once told me that she had been rung up late at night by the Liverpool police to warn her that somebody was impersonating her husband, loitering in a dangerous and drug-infested area of the city with a crowd of Rastafarians. "That's my Paddy," she instantly replied.

But his very isolation from the main currents of Westminster has enabled Ashdown to think widely and speak with rare freedom. His weekend speech was typical of his best in being thought through, vivid, provocative and even, in key parts, plausible (thus breaking every important rule of contemporary political rhetoric).

Briefly put, it started with the familiar thought that globalisation and individualism had between them changed our world. The old model of politics, by which "governments could, by and large, deliver what their people wanted; and so people, by and large, believed in government" was being destroyed.

But, whereas most politicians adopt a mournful or reactionary posture when confronting this thought, Ashdown sounded positively chipper: "The age of deference, if not quite dead, is dying on its feet. And the age of the individual is coming along famously. We're seeing the beginning of the end of the politics of class and nation."

The Conservatives, he said, were responding to globalisation by trying to make Britain ever more free-market, a smaller version of the United States, with its ghettos and widening social rifts. Labour was trying to create a new "state-sponsored morality - to rebuild Britain in the image of Singapore". The real answer, however, was a politics based round "self-reliant individuals", a politics of education, reform and tolerance.

Thus far, the speech pursued traditional Liberal tactics, painting the two big parties as extreme, and proposing a "sensible" middle-of-the-road alternative. However, when Ashdown listed the policies his individualist party was actually committed to, they sounded identical to new Labour's. On education, support for small business, long-term investment, welfare reform, constitutional change, this was a speech that could have been made by Tony Blair.

It was only when he turned to morality and power that Ashdown sounded a truly different note, laying savagely into Jack Straw's censorious approach to idlers, sturdy beggars and other undesirables.

The emphasis on people's responsibilities, rather than their rights, begins well enough, he said. "But it ends by telling people how to live their lives - by limiting freedom of speech, by spot fines for chewing gum and neglecting to pull the lavatory chain. It ends in policies which punish the sinner but ignore the sin."

Attacking new Labour's illiberal streak would be less impressive, had Ashdown not marked his party out by taking some brave specific stands, notably on gays in the military. This is unlikely to do him any electoral good. But, as on drugs, censorship, civil liberties and other issues, the Liberal Democrats here show themselves genuinely principled.

We don't yet have a word for it, but there is a code that reverses some traditional teaching, yet is clear and principled itself. It abhors homophobia rather than homosexuality. It rejects beliefs about women, racial differences, Hell and sin that underpin Judeo-Christian teaching. It is "liberal" in a way that owes more to Bloomsbury and Martin Luther King than Gladstone or Adam Smith.

More than economics, voting reform or localism this provides the core belief-system of the Liberal Democrats. Ashdown spoke of a society that would "encourage diversity ... accommodate different lifestyles ... be heedless of gender or sexual orientation. It will celebrate experimentation. And it will value pluralism and the wide richness of ethnic traditions and cultures in Britain today." New Labour would agree, in principle, yet never use those words. That is not the enthusiasm of the communitarians and social moralists of the left, searching for security in a turbulent world.

There is an important division opening in politics between individualism and community, between freedom and security, between those who stress rights and those who stress duty. It is not a normal left-right division. It zig-zags through the Labour Party and through the Conservatives. Both have libertarians and moralists in their ranks.

It fractures the uncommitted majority of thinking society, too. It is very much a thing of our uncertain, harassed times. It could be caricatured as the division between people who enjoy Tarantino films and people who worry about them, or between natural born rebels and natural magistrates.

And the rebels have cast Blair and Jack Straw as the villains of the drama, puritans whose instincts are as authoritarian as Oliver Cromwell's. At one level, Ashdown's speech could be summarised as "the Lib Dems equal Labour minus Straw".

In fact, both Straw and new Labour generally are about much more than populism. There is a wider yearning for security, order and greater social trust that is felt on the streets and preached by economists, think-tanks and intellectuals. It is not the centrally imposed morality that Ashdown attacks, but it certainly is a response to his twin forces of globalisation and individualism.

And the Liberal Democrats are against it. After their Nottingham conference they look ever more like the libertarian party in British politics. This is probably a niche market, but it is a very important niche for someone to stand in.

As a bit of a puritan myself, I am glad that Ashdown is standing there. We are undergoing that dreary narrowing of the political agenda that precedes a general election and he is a cheering addition to the game. At least some of what he says doesn't seem calculated for party advantage. Indeed, after Nottingham, he seems intent on becoming, in the appropriate jargon of political correctness, "differently popular".

And if a Labour government ever was dependent on Ashdown votes, we know what sort of influence he'd aspire to be - in the darkest watches of the night and the darkest corners of Whitehall he would be a safeguard against illiberalism or authoritarianism. These days, the Labour left worries desperately about the prospect of having to share power with the Lib-Dems. I really can't see why.