He was like one of those characters in an 18th-century comedy meant to embody a particular flavor of human folly. Trump struck me as adolescent, hilariously ostentatious, arbitrary, unkind, profane, dishonest, loudly opinionated, and consistently wrong. He remains the most vain man I have ever met. And he was trying to make a good impression. Who could have predicted that those very traits, now on prominent daily display, would turn him into the leading G.O.P. candidate for president of the United States?

His latest outrageous edict on banning all Muslims from entering the country comes as no surprise to me based on the man I met nearly 20 years ago. He has no coherent political philosophy, so comparisons with Fascist leaders miss the mark. He just reacts. Trump lives in a fantasy of perfection, with himself as its animating force.

When asked how he intended to fund the expensive life of a costumed avenger, it was pointed out that Parliamentary expenses are ‘surprisingly flexible’.

“You had your chance,” said Clegg in a recorded message left pinned to the chest of an unconscious Green Party councillor.

“You could have chosen to follow good men, like Gladstone and Vince Cable.”

“In five years time you’ll look up from your Conservative government and factional left/ right squabbles and shout save us!” he added.

“And I’ll look down and whisper; No.”

“The polls are also looking good,” Nuttall continued. This provoked several sharp intakes of breath, before everyone realised he hadn’t been talking about the Poles. To make up for this momentary lapse, they gave Ukip supporter Harjit Singh a standing ovation for being a Sikh.

Elsewhere there was nothing but trouble. Our fish were being stolen, our nuns were being sneered at, our vacuum cleaners were being abused and our foreign aid budget was being spent on teaching Africans to dance. MEP Nathan Gill proudly introduced his new publication, 8 Reasons for Cutting Foreign Aid that featured a photo of a starving African child on the front. “Charity begins at home,” he said. Even our dogs were going to the dogs. All those fancy new cockapoos and labradooodle what nots.

Into this hellish pit of despair, stepped a heavily made-up Nigel Farage…

In the decorous company of sixth-formers or international businesspeople, Farage will insist he isn’t against immigration, or Europe, or Europeans – only against British membership of the European Union. Being anti-immigration, he has said, would be ‘moronic’. He says he wants a Switzerland-style trade relationship with the EU, and an Australian-style immigration system, based on points, with the world: fewer Polish builders, more Indian scientists. But this isn’t the message Ukip is putting out on the street, where, as Lord Ashcroft correctly noted, EU membership isn’t an issue. Immigration is. All immigration. Foreignness. Otherness. ‘Say no to mass immigration,’ a Ukip flyer in Thanet says. Rumours and urban legends about victimised indigenous Britons and pampered foreigners fly across the internet. Hate anecdotes in the right-wing press become generalised: if one foreigner is found to be cheating the system, there must be thousands like them, millions. Farage is the beneficiary. Ukip’s discourse isn’t so much a dog whistle as the full dog orchestra.

The argument that says the UKIP represents a rebellion against the political elite seems true (aside from its public school-educated/banker/professional politician leader), but even that lends it a sophistication it barely deserves. UKIP is the road rage of a repressed parochialism; the collective panic attack of an introspective minority that has watched a succession of socially and economically liberal governments and their co-religionists in the media promote a world-view that seemed to leave these “outsiders” further and further in the margins.

The margins of culture, that is. Not the margins of the economy. One suspects many of UKIP’s leading figures are businessmen and women who have done rather well out of the post-Thatcher economic consensus. Conversely, UKIP supporters from poorer parts of society are not disadvantaged because of EU red tape, immigration or tolerance towards gays, but because they live in a low-skill, wildly free market economy that has been propagated by every government – to a greater or lesser extent – since 1979, creating an entrenched inequality that is worsening every year.

After the broadcast of Curtis’s 2007 film The Trap, which traced the influence of game theory – the idea that humans behaved as self-interested individuals – on contemporary economic thought, Prospect magazine’s Max Steuer argued that the series “greatly exaggerates the power of ideas, and at the same time almost wilfully misrepresents them”. Others made similar criticisms of All Watched over by Machines of Loving Grace, which linked the anti-state philosophy of Ayn Rand with the “techno-utopians” who developed modern computing. At the very least, don’t his films encourage precisely that gloomy feeling – a sense that power is in the hands of an unaccountable elite – that so exercises him?

“Well, I am a creature of my time,” he concedes. We’ve found our way to a café in the shopping centre near Thamesmead, where we can chat at greater length. “What I’ve been trying to do is analyse why progressive ideas failed.

“Secondly, I’m interested in telling stories, because I like telling stories and I think ideas are important. I take particular influences of particular groups of people as a way of showing how that idea spread out. I never say this is where it all came from, this shadowy group of people. I’m telling you a story, like a novelist would, but as a factual story to try and bring it to life to you.”