There is a class of politicians known as the leaders who never were, to which can be added the name of Liam Fox, whose fall illustrates how swiftly a politician can go from being yesterday's rising star to today's has-been.
He emerged as a potential future leader soon after the Conservatives lost office, when the new party leader, William Hague, reshuffled his Shadow Cabinet for the first time in June 1998. Hague was only 37 years old and had hitherto been the youngest member of his own top team. After the reshuffle, there was one member of the Shadow Cabinet younger than the leader – 36-year-old Mr Fox.
His swift rise from back bench to front bench was partly down to sheer ability, but aided by his Scottish accent. One of the issues looming on the political horizon was Labour's intention to hold a referendum on devolution in Scotland. The Conservatives were to be at the head of the No campaign, but the 1997 Labour landslide had left them without any MPs north of the border.
Though Mr Fox represented an English seat, having been elected MP for Woodspring, in Somerset, in 1992, he was at least a Scot. In 1997, he was appointed deputy spokesman on constitutional affairs with special responsibility for Scotland.
While he was campaigning against devolution, he is thought to have come into contact for the first time with Adam Werritty, an undergraduate at Edinburgh University.
The Scots did not heed Mr Fox's message that a devolved Scotland would make the UK "unstable" – but all the same, he emerged from the campaign with his reputation as a street fighter enhanced. Promotion to the Shadow Cabinet soon followed, and the talk in Parliament was that the next Conservative Prime Minister had arrived.
He had the slight handicap of being in a crowded field, which has thinned out over the years. There are not many out-and-out Thatcherites in the present Government because a third general election defeat drove the Tories back into the political centre ground. But the first of those defeats, in 1997, had the opposite effect.
The pent-up frustration with John Major made a Thatcherite of almost every Tory except Ken Clarke, yet even then there was a rift developing on the party's right, between those who wanted to combine free-market economics and Euroscepticism with a more relaxed view on social issues such as sex and marriage, and those, including Mr Fox, who was raised a Roman Catholic, who were social conservatives.
Having lost the Scottish referendum, he became an unexpected advocate for devolving to the Scottish parliament the power to set the law on abortion. His reason was tactical: he calculated that Labour would come up against more opposition to relaxing abortion law in Scotland, where there is a strong Catholic presence, than in England.
Something else about Mr Fox which did not stand out then, but does now, was his social background. In contrast to most of the present Cabinet, he grew up on a council estate in East Kilbride. Both his grandparents were miners; his father was a teacher. His family was not deeply political, but were mostly Labour supporters. One of his uncles was the Labour provost of Motherwell.
He became interested in politics in his teens, around the time when he entered Glasgow University as a medical student. There he was president of the Conservative Association, and a member of the Students' Representative Council – from which he resigned, in circumstances that later became notorious.
When a gay and lesbian society applied for admission to the Glasgow University Union, its president, Vince Gallagher, announced: "We don't want poofs in our union." The student council passed a resolution condemning this offensive comment, whereupon Mr Fox resigned, and was quoted in the student newspaper as saying: "I just don't want gays flaunting it in front of me, which is what they would do."
When the Commons voted in 1999 to reduce from 18 to 16 the age at which gay sex is legal, and in 2000 when MPs voted to repeal the notoriously anti-gay Clause 28, Mr Fox was one of the minority who voted against the changes.
Years later, rumours started to circulate about his own bachelor status. He left it until the age of 44 before getting married to Jesme Baird. Shortly before his wedding, at which Adam Werritty was his best man, Mr Fox admitted in an interview that there had been gossip about his sexuality.
"They'd say, 'Why are you not married? You must be a playboy or a wild man or gay.' It's perfectly clear that Jesme and I are very much in love. I'm not going into that smear territory," he said.
But it was not the gossip that prevented Mr Fox from becoming party leader: it was the absence of opportunity. Before 2005, when he was successively shadow Health Secretary, party chairman and shadow Foreign Secretary, there was always someone more senior to fill the role of favoured candidate of the Thatcherite right.
Though he put himself forward as a leadership candidate in 2005, he was eliminated on the second ballot having fallen a few votes behind his rival right winger, David Davis.
It was only when Davis pulled out of the Shadow Cabinet that Mr Fox, who had been shifted by David Cameron into a slightly less senior position as shadow Defence Secretary, became the torch bearer of the Thatcherites.
His position as the defender of the faith was sanctified only a month ago, when he turned 50 and Baroness Thatcher, who had missed her own 85th birthday party hosted by Mr Cameron in Downing Street, emerged from isolation to be at his birthday party.
Whatever the strange personal relationship was between Mr Fox and Mr Werritty – his younger by 17 years – there is no mystery about their political activity. Together they were doing their best to keep the Government's foreign policy true to the Thatcherite tradition of antipathy to the EU and a strong alliance with the US – in particular with the Republican Party.
As Defence Secretary, Mr Fox went out on a limb to protect the armed forces as best he could from spending cuts. His admirers also praised his handling of the conflict in Libya, where no British lives have been lost. Yesterday, friends said we should not assume that the political career of this durable Scottish Thatcherite is over yet.
Fox Hunt: 10 Days That Destroyed The Defence Secretary
Mr Fox is said to have put national security at risk after it emerges Adam Werritty had access to the Ministry of Defence and was distributing cards describing him as Mr Fox's adviser, despite not having security clearance.
Mr Fox dismisses the accusations as "baseless", but orders the MoD to carry out an inquiry into them.
Pictures emerge of the pair meeting officials during a visit to Sri Lanka, while Mr Fox bats away questions about the affair while in Libya. The MoD says Mr Werritty was present at a public lecture given by Mr Fox, but not at any official meetings.
It is claimed Mr Werritty organised a meeting in Dubai between Mr Fox and a company interested in selling equipment to the MoD, at which no officials were present. David Cameron asks to see the report into Mr Fox's conduct .
Mr Fox admitted he was wrong to attend a meeting with the leader of a private equity firm arranged by Mr Werritty. He also recognises that the "misleading impression" could have been given that his friend was an official aide.
Mr Fox admits to Parliament that Mr Werritty met him at the MoD 22 times in 16 months, eight times more than previously acknowledged, and joined him on 18 foreign trips during the same period. He apologises.
The self-styled adviser is interviewed by Cabinet officials as part of inquiry.
More damning headlines after senior Israeli diplomats say they thought Mr Werritty was the Defence Secretary's official adviser when they met the pair for a major conference on sanctions against Iran.
Mr Fox only appears more vulnerable thanks to aides briefing against Mr Werritty, describing him as a "Walter Mitty" character, in an attempt to protect themselves.
As Mr Werritty is questioned again, claims his travels were funded by lobbyists – after Mr Fox insisted his friend was "not dependent on any transactional behaviour to maintain his income" – finally push the Defence Secretary over the edge.
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