What people don't realise," says Vince Cable, "is how varied an MP's life is." That's an unusual choice of adjective. Notice that he is not complaining that the life of an MP is hard, underpaid, subject to constant press intrusion and so on. Here is a man past normal retirement age quietly satisfied that he has a vast amount of work to do – such as meeting a gangster who is worried because some other criminal wants him dead.
After a brief chat in Cable's home in Twickenham in west London, we drive off to see his assistant, Sandra Fayle, who helps with constituency work. They discuss visitors to the previous Friday's evening surgery, a regular slot in Cable's diary, which gives a cross-section of Twickenham's population, including the good, the mad and the bad, the chance to bring their problems to their local MP.
Cable has at his side, on Fayle's dining-room table, a pile of buff folders, each marked with the name of a constituent and containing notes about that person's particular concerns.
"Ah, this is a weird one," he says, opening another folder, a half smile playing across his round, wrinkled face, as if he finds the story quizzical but not actually funny. "This guy's a gangster, a serious gangster. He had a wonderful tale. He talked about his driver, who had killed five people. He had to let him go, because he was too violent. The particular problem he has is that somebody has taken a contract out on his life."
What? In 2008? In Twickenham?
"The police are taking this quite seriously," Cable says. "They have advised him to take precautions. What he wants to find out is who it is who's got this contract out on his life."
On television, Vince Cable comes over as a voice of quiet authority born of experience. He is to political spin what John Sergeant is to ballroom dancing. He is not young. To be cruelly blunt, he is not handsome either, with that face like a collapsed pudding. Most of his hair parted company with his skull years ago, and such wisps as cling on around the back of the head are iron-grey. He lacks a photogenic young family to put before the cameras for a self-aggrandising Christmas card, and he does not know how to rattle off political nostrums with that slick confidence that the leading politicians learnt in their university debating societies.
Despite his addiction to work, Cable finds time for one serious hobby. For years, he has been going twice a week to a dancing school in Hampton Wick for lessons in ballroom and Latin dancing. His late wife used to be his dancing partner. Rachel Cable, his second wife, has taken her place. When he is asked to assess for himself how good he is, Cable claims to be "better than John Sergeant, but not as good as the stars of the ballroom". But you don't have to take his word for it; on YouTube, you can find a clip of him twirling around the dance floor with last year's Strictly Come Dancing winner, Alesha Dixon. "He clearly knows his steps. He enjoys what he does. He looks like he's not afraid of a bit of hard work," Dixon reckons.
Even before Sergeant's notorious appearance on this year's show, Cable had confided to the BBC that he would like to compete. It has been suggested that he might have won, but the hoped-for invitation never came. Giving a practising politician that kind of exposure on prime-time television could have landed the BBC with problems it did not need. "I think it would be too controversial," Cable concedes. "From their point of view, they see all the dangers, because they would have other parties demanding the right to go on, and people would start using the programme for political ends."
Well, maybe there should be an election special Strictly Come Dancing, with Cable dancing for the Liberal Democrats, Lord Mandelson of Hartlepool and Foy representing Labour, and for the Conservatives, perhaps, Ann Widdecombe.
Nonetheless, Cable has carved out a television role with rather more gravitas. Note how, after the commentators have asked Alistair Darling to defend the Government's handling of the recession, and George Osborne to trash the same, they turn to Vince Cable as the person who can quietly, reliably, intelligibly and intelligently explain what the hell is going on. In an age when public regard for politicians is at rock bottom, the Lib Dems' shadow Chancellor has a rare quality – people trust him.
It must have been this aura of quiet authority that made the local gangster think he could go to Vince Cable for vital information about the feuds and hatreds in the underworld. Cable and Fayle agree that a letter to the local CID head is in order. The letter will enquire about this underworld contract (without necessarily expecting the police to tell them about it), and will stress that, as the local MP, Cable would not want to see any of his constituents rubbed out by a hit man.
Other stories from the pile of buff folders are more prosaic, but still important to those concerned. One is from a retired police officer whose record is so clean that he has never had so much as a parking ticket in his life, but he has copped an automatic fine after a camera spotted him in a bus lane. He has a plausible reason for being there, but you cannot explain that to a camera.
Then there's the elderly couple living by a golf club who understandably object to the frequency which their windows are broken by stray golf balls; and a woman on income support whose sister borrowed her car and ran up £1,300 in fines; plus two youths who are joining the Peace Brigades volunteers in Guatemala and want an emergency number they can call if should they find themselves in danger – and so on.
Every week, Cable, 65, handles between 15 and 20 such cases face to face, as well as trying to keep up with a huge volume of correspondence. One day, when the economic news was particularly dire, 750 emails dropped into his in-box.
Vince Cable lives simply in Twickenham in a house he bought 35 years ago for £12,000. On working days, he walks to the railway station to take the commuter train to Westminster. His house is obviously now worth a large multiple of what he paid for it, but it is not one of those million-pound-plus properties that abounded in west London during the property boom. Its value is diminished by recession, and by being within shouting distance of Twickenham rugby stadium. On match days, 80,000 people pass in front of his gate, and he can find himself caught inside a police cordon.
As I arrive at his home, just before 9am, he and Rachel are still at breakfast. His day has started late because GMTV cancelled a studio interview at short notice. Not far behind me are two of his constituents, one of them a freelance journalist who wants to interview him for the financial press.
When they are gone and he has completed his constituency business, we head for Westminster, where he is meeting the Liberal Democrat leader, Nick Clegg, and David Laws, the party's education spokesman, to go over an early draft of a policy document.
Next, he has meetings with two constituents, and then it's into the Commons chamber for the debate over the police raid on the offices of the Conservative MP Damian Green, after which it's back to Clegg's office for another meeting, then a dash up to his third-floor office, where a party officer named Issan Ghazni is waiting to see him.
Issan, like Cable, is a defector from the Labour Party (but of more recent vintage) and an illustration of how times have changed. Cable left in 1982 because Labour was veering to the left and obsessed with world affairs at the expense of everyday problems. Issan left in 2003, for the opposite reasons: "Iraq was the last straw," he says.
Today, Issan has two little lists – seats where they hope to get a Liberal Democrat from an ethnic background into Parliament next time round, and seats where he is aiming for what he calls a "two-election victory". He would like Walthamstow in east London, Birmingham Hodge Hill, and Leicester South to be on the first list, with Luton South and Birmingham Perry Barr on the second. This entails a decision about where the Liberal Democrats concentrate their thin resources at the next election. The party is short of millionaire backers, and has experienced some well-publicised problems with the few they have, but there is a Rowntree Trust grant to the party to be used to improve its ethnic and gender balance. Cable listens without committing himself.
Next, there are telephone messages to be answered, from more people with demands on Cable's time. His new status as the Liberal Democrats' biggest asset takes him out of London more often than he would like. He has seen 10 towns or cities in the previous five days, including a large fundraising dinner in Newcastle upon Tyne. Between now and Christmas, he must sign 500 Christmas cards to party members and other helpers. After Christmas, he is hoping to complete a book on the economic crisis. Understandably, then, at least one caller got a polite but definite "no".
Cable's parliamentary office is on the third floor of Portcullis House, the building that resembles a giant radiator on the corner where the Victoria Embankment meets Westminster Bridge. He has two adjoining rooms. The outer office is cramped, because it is really only big enough for one or possibly two assistants, but Cable has three, all young. The shelves are crammed with boxes of papers. Hanging on the wall, where another MP might choose to have a tasteful work of art or a boastful framed photograph of himself, Cable for some reason has a map of the British railway system. His office is bigger, with a sizeable desk at the window, while nearly half the room is given over to a table where up to six people can comfortably hold a conference.
The outer office fills with four guests, all experts in the law as it affects the education of children with learning disabilities. Cable has arranged for them to meet the Secretary of State, Ed Balls, at 7.15pm, which leaves them just 20 minutes to decide what they want to say to the minister.
Anyone who has ever brought together four experts with strong opinions on an emotive subject will know that bringing their conversation to a conclusion in 20 minutes is a challenge. It puts Cable in the unusual position, for a professional politician, of being the one person at the meeting who will not offer an opinion. He looks at his watch a couple of times, and gently reminds the gathering that they must concentrate on just two or three main points they want to make when they are in the Secretary of State's office. "We won't have long in there, and Ed Balls is a loquacious fellow," he warns.
It is a tribute to his chairmanship that by the 19th minute, they have agreed what they want to say, and who will do the talking.
When the meeting with Balls is over, there is one more item on Cable's diary for the day – a working dinner scheduled for 8.30pm with Danny Alexander, who is in charge of drawing up the party's next election manifesto.
Vince Cable entered Parliament quite late in life, in 1997, aged 54, against the background of a family tragedy. In 1964, in the long vacation after he had graduated from Cambridge University, he'd gone to York to work temporarily as a nurse in a home for the mentally ill. He'd met Olympia Rebelo, who was studying at York University. She was a Kenyan Asian. His first serious job saw him billeted in Kenya, advising the government as a treasury economist.
They met again in Kenya, and married. This horrified Cable's father, an upwardly mobile working-class Tory who had progressed from being a joiner to lecturing at technical college, and had archaic views about race. Olympia's parents, who were Catholics but had a few ideas about caste, were not thrilled either. But the marriage lasted for more than 30 years, producing three children now in or near their forties, and two grandchildren. Olympia's influence is visible in the Cable home, where there is a quantity of Indian art on display. On the floors, there are valuable-looking hand-woven Indian carpets.
In 1987, Olympia was struck down by cancer. It seemed to go away after chemotherapy, but came back more virulently. For seven years her condition deteriorated, until Cable had to pump air into her lungs up to four times a day. Then her bones gave way, and she had to use a wheelchair. She died days after the 2001 general election.
"It really was a terrible period," he says, with a shudder. "That election was really dreadful. Fortunately, I had a lot of activists to carry me through, and she was always so positive."
After Olympia's death he became "hyperactive", rushing from one speaking engagement to another, including a visit to the New Forest to talk about the United Nations and Third World development. After he had spoken, he was drawn into a fierce argument with a woman in the audience. He recognised her as a fellow student from Cambridge, Rachel Smith. They are now married. She lives with him mainly at weekends; in the week, she runs a farm in the New Forest.
Cable had not intended to make such a late entry into national politics. He was a promising student politician, and in the early 1970s was a Labour councillor in Glasgow, with his eyes on a parliamentary seat. But the Labour machine did not then look kindly on clever young Oxbridge graduates with no trade union contacts. So he headed south, and was a political adviser to John Smith in the last days of the Labour government.
He transferred to the Twickenham Labour Party just as the party was going through a strange phase across London. "I thought the Liberals were putting up the best opposition to the Conservatives in Twickenham," he said. "I liked their grass-roots, bottom-up style of politics. At my last Labour Party meeting, there had been trouble between the USSR and China, and the party agreed to send letters to President Brezhnev and to Mao's successor warning that they were causing disunity in the socialist camp!" He quit Labour for that half-forgotten 1980s creation, the SDP, which merged with the Liberals after six years to form the Liberal Democrats.
That kept him out of full-time politics for the best part of 20 years, and makes it unlikely that he will ever be a government minister – unlikely, but not altogether impossible. The next election could produce a House of Commons in which, for the first time in 30 years, no party has a controlling majority. A former Liberal Democrat leader, Paddy Ashdown, rather optimistically hoped this might happen in 1997, and wanted a coalition with Labour in which a few Liberal Democrats took cabinet jobs. Not all Liberal Democrats wanted to sup with Labour, but Vince Cable was very much in favour.
This time, he hints, he would want to do the same deal with whichever party, Conservative or Labour, emerged with the larger number of MPs. It is obviously in his mind that such a deal could, belatedly, elevate him to the status of cabinet minister. But it is a long shot and, as he says: "If it doesn't happen, it doesn't happen."
He does not regret the career choice that has kept him out of government, because the political reality now is that to win one of the lead jobs in either main party, you have to enter politics full-time directly on leaving university and stay there for life. Gordon Brown was the student rector of Edinburgh at the age of 21; at the same age, David Cameron was employed by the Conservative research department.
"Osborne, Cameron, Hague – they are all professional politicians who have not done very much outside, and I think it's true of Labour also," Cable says, as we take the train from Twickenham. "Tony Blair was a serious, rounded character, but the others haven't done very much. I know it's always easy to see the past in rosy colours, but the [Harold] Wilson generation was so much more impressive, all sorts of larger-than-life, major characters – [Anthony] Crosland, [Dick] Crossman, [Denis] Healey. It's difficult to see that sort of depth these days."
The Liberal Democrats persuaded him to be their candidate in Twickenham for the 1992 election, which he could be without interfering with his well-paid job at Shell. Somewhat to his own surprise, he knocked a large hole in the Conservative majority, which he then overturned in 1997.
He was launched as a national politician during last year's convulsion in the Liberal Democrat party, when Ming Campbell resigned from the leadership. Vince Cable was his deputy – chosen, it was very unkindly suggested, because he was the only senior Liberal Democrat who would not look young next to Ming. He was left in the hot seat for a few weeks, keeping the party together during a closely fought leadership contest and taking on Gordon Brown at Prime Minister's Questions. He sealed his reputation with one devastating remark when, in a voice that one commentator described as "like a sheep with stomachache", he said: "The house has noticed the Prime Minister's remarkable transformation in the past few weeks – from Stalin to Mr Bean."
Cable admits that, as he rode that wave of success, he thought about entering the contest to lead the Liberal Democrats. However, the party appeared to agree with what they were told in the newspapers – that Campbell's leadership failed because he was too old. Cable did not think that was the real problem, but he could see that the party was not going to choose a new leader only two years younger than his predecessor. He appears to have settled comfortably into his role as a deputy who is older, wiser and arguably better known than his leader.
His explanation of his success is simple and humble – what else would you expect from Cable? "I think it's partly luck. I happen to have built up a fairly good reputation in economic matters at a time when this became the big issue of the day. Most of that time, people weren't very interested in economic policy, quite frankly.
"The other thing that has worked is that I did anticipate a lot of the problems we are now facing. I was involved in the campaign against the demutualisation of the building societies. Ten years later, we are seeing the effect.
"And I did, a lot, in Parliament, point out the instability of the banks. In 2003, I raised with Gordon Brown the issue around the very rapid growth of British household debt and the bubble in house prices. He swatted all this away at the time. In retrospect, this was the right thing to have said."
In other words, when other politicians were chasing issues where there were votes to be had, Vince Cable was quietly beavering away on a dull, difficult but vitally important subject, on which he has been proved right. He calls it "luck". Others might say that it was hard work and good judgement. It's a shame that there are not more people in Parliament like him.
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