Nick Clegg, who last week was elected leader of the Liberal Democrats, certainly has a quirky character. He left the European parliament because he wanted to return to domestic politics working for a party which dealt in “big ideas”. Let me remind you that this is the Lib Dems we are referring to. Then, having said he has no faith, he insists that his two children are taught Catholic dogma. Oh, and he firmly believes the Lib Dems will be in power within a decade.

Clegg, who has reached the top of his party at the alarmingly young age of 40, is a thoroughly charming chap. Convivial, confident, cultured. The sort of person with whom a chat at a dinner party would be rather entertaining. Personable, famously conversant in five languages, Clegg likes the theatre, watching television with his young sons and walking in the Peak District. So, a normal, middle-class family bloke who is probably funky enough to use male grooming products, but not outrageous enough to take illegal drugs (the usage of which while at university is a taboo area).

He is probably a bit brighter than most and definitely more upper-middle-class than average, if you take his aristocratic Russian grandmother, posh education at Westminster, Spanish wife and nannied-up household into account.

However, get him going on politics and Clegg’s appeal rather starts to wobble. Where shall we start? How about in 2004 when he decided to leave Brussels and his job as MEP for the East Midlands.

“After a while I thought, I am in the wrong place,” he says. So he comes back to London and the throbbing heart of the Lib Dems; a party that has so little sway over the hearts and minds of the British public that it barely features in the opinion polls and is so undynamic that only 60% of its members bothered to vote in the Clegg/Chris Huhne leadership contest. (Which culminated with Clegg winning by a paltry 500 votes.)

Never mind. The Lib Dems might represent but a dim imprint of the Liberal party’s glory days but Clegg, elected as MP for Sheffield Hallam in 2005, had at least achieved his aim, which was to reach the House of Commons where he could get to grips with the “big debates of the day”. He was quickly made a Lib Dem front-bencher and set to work “trying to make the big case”.

Now, I’ve never really understood what the “big case” is for the Lib Dems. Interviewing Clegg should be the ideal time to find out. “Let’s take the big issues,” he says. Oh dear, I know what is coming: all those radical ideas that the Lib Dems first came up with that everyone else has now copied. “But it makes a difference!” he cries. “We were speaking about the environment years before anyone else. You can shift the debate in a big way, if you are right, and if you get onto things much earlier than other parties.”

So is that what the Lib Dems are for - shifting debate? “No!” Well, what then? “To make Britain more liberal. It’s as simple as that. Britain is not a liberal enough country. Civil liberties are trashed. Kids born into deprived areas are literally condemned at birth. That’s not liberal. It’s not liberal that things are decided by Gordon Brown and a bunch of acolytes behind closed doors in London.”

Surely the prime minister and his government are our democratically elected representatives? “It is not liberal. A liberal society is one in which families and communities have power over their own destiny,” he continues, sounding a bit like Captain Kirk. “I advocate seriously radical decentralisation. Get rid of council tax. Allow people to raise taxes locally.”

What, so that financially challenged boroughs such as, say, Hackney in east London would have the onerous burden of raising their own taxes? “Well, you would make sure that such places are not only reliant on the funds they can raise locally,” he admits. So his decentralisation isn’t that radical, then.

At this juncture we start to canter through all the things that we, the benighted public, would have power over were we to live under a Lib Dem government: taxes, education, health. Choice coming out of our ears. Votes for everything. Ballot boxes springing up at every moment. Blimey, I think, we’d hardly have time to keep our day jobs alive.

Is not this all just wishful thinking? Surely the only way that the Lib Dems are ever going to have a sniff of power is by cosying up to that nice Mr Cameron, whose ideas about personal choice over health and education are perilously close to Clegg’s anyway. Is Clegg trying to smooth the way for a coalition? “No!” he says. Clegg’s plan is bigger than that. Much bigger.

“My objective is to break the two-party system. We can do that in two elections.” My, that’s a boast. How? By cosying up to the soft Tory underbelly in the southeast of England? Homing in on the disaffected Labour urban areas of the north? Neither. “One of the exciting things about politics is that automatic tribal loyalty to one party or another has gone. And it was tribal, class-based politics that sustained the two-party system. So you have got a society that is changing and a political system that hasn’t. And at some point the political system will have to change.”

What are your tactics for storming No 10? “Oh, tactics, schmactics,” says Clegg, weirdly. All right, let’s put it differently. What are your plans, your policies? “Oh, to make the party bigger,” he says airily. In what way - party members, MPs? “All that. I will hold American-style town hall meetings wherever I go. I hope people will genuinely come and tell me what their priorities are, people who have really good ideas and really strong feelings about the way things should be changed.”

Actually, let’s not bother about tactics, or even schmactics, because Clegg believes that everyone will come round to his way of thinking. Forget the fact that we haven’t had a Liberal government for about 90 years. According to Clegg, voting Lib Dem is “in our blood”. Funny that so few of us do it then.

“There is a liberal temperament in Britain.” Our liberal temperament, for those of us who didn’t realise we had one, sounds like a cross between Shami Chakrabarti, director of Liberty, the human rights organisation, and a grumpy listener to the BBC’s Today programme: “Being quite bolshie, not liking arbitrary authority, whether from London or Brussels. Really disliking faceless, insensitive bureaucracy, the erosion of British civil liberties and the heavy hand of the state.”

And fairness: “People don’t like it when things are unfair. When you have grinding poverty cheek by jowl with Olympian global wealth. People feel that’s wrong.”

Is he a wealth warrior? “Well, there are a lot of loopholes for the super-rich which should be tightened up. Of course you shouldn’t squeeze them until they leave. But you should have one flat tax on nondomestic earnings of 10%. And that money should go directly to cutting council tax for people on the lowest incomes,” he finishes with a flourish. Oh, here we are. Back to cutting council tax again, which by now sounds like the only solid idea in his arsenal.

Luckily for him, Clegg is interested in bigger things than boring old policies. “The political establishment is really skating on thin ice. Everyone is underestimating the profound sense of alienation and frustration in the country. Let me tell you a few stories,” he says, plunging into a series of wearying anecdotes about people in his constituency who are having problems with automated answering services and other assorted horrors of modern life. All of which the Liberal Democrats - naturally - will offer sanctuary from.

Will they really be in power? “Yes. Politics is broke. It is just broken. Look at the trend over the past 50 years. The proportion of people voting for the two larger parties has gone down remorselessly.” Yes, but that doesn’t make them vote Lib Dem, does it.

Perhaps they are apolitical because they are quite happy with their lot, I suggest. After all, we are richer, better clothed, better fed and better holidayed than ever. “People are not content,” says Clegg. “There is a great level of alienation, anxiety and frustrated potential here. There are thousands of children condemned by the circumstances of their birth.”

We have a brief chat about what Clegg calls “our segregated educated system”. Interestingly, he rejects the idea that our public schools, which cream off the best pupils and the best teachers and enjoy charitable status while doing so, are in any way responsible. Apparently, what is wrong with our education system is we haven’t got our “building blocks” in place.

“It’s not rocket science,” he continues, citing a book that he wrote after a fact-finding trip around primary schools in Scandinavia and Holland. “Public schools are a London issue. That’s not where the problem lies.” Would he send his children to private schools? (The eldest, aged five, is at a state primary.) “I am not going to hold his education hostage to my politics,” he responds. So that’s a yes. “I am not going to play politics with my kids. I am not going to use my strong sense of principle as a means to hijack ...”

The trouble with Clegg is that although he enjoys spouting about “the big picture”, it’s not quite clear that he has thought the big picture through.

Last week The Guardian called his ideas “crisp”, but after an hour in his company I feel that “waffle” might be a more appropriate carbohydrate snack. The Clegg mind may have been brilliantly honed at Westminster and Cambridge, but it is now dismally weighed down by unleavened bagginess. I feel like sending him off on a long walk in the Peak District in the company of Fowler’s English Usage, if only to help him banish the clichés and meaningless verbiage which litter his utterances.

He makes a big deal about being more human than his fellow politicos. How will this be revealed to us? “To be as clear and articulate and passionate as I can about what my values are and what I think a liberal Britain could look like. And why I trust in the fact that a lot of people will like that.” Don’t tell me. It’s not rocket science.

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