Iain Duncan-Smith: Shadow Defence Secretary

By BBC News Online's Ben Davies

Iain Duncan Smith is one of standard bearers of the Thatcherite right.

An ardent free marketeer with distinctly anti-Europe Union views he was the ideal man, in many ways, to take over the Chingford seat of Baroness Thatcher's street fighting sidekick Norman Tebbit when he stepped down at the 1992 election.

As a former captain in the guards, Mr Duncan-Smith was a natural choice to speak for the Conservatives on defence matters - despite the fact that he backed John Redwood and not William Hague for the Conservative leadership.

Redwood backer

Mr Redwood had first run for the leadership after John Major famously, if ineffectually, tried to bring the warring sections of his party together by challenging them to "put up, or shut up".

Mr Major subsequently won the contest and then went on to spectacularly lose the general election. .

Mr Duncan Smith supported John Redwood for the Tory leadership

When Mr Redwood was knocked out of the subsequent leadership competition in the wake of the 1997 general election, Mr Duncan Smith, who had run his campaign, eventually backed William Hague and reaped the reward with a frontbench job.

As social security spokesman he was a leading part of Tory opposition to major planks of the government's programme such as welfare to work.

Anti-euro

His strong anti-EU beliefs were the driving factor behind his consistent refusal to join Mr Major's government.

His decision not to vote with the government over the Maastricht treaty, just after becoming an MP, aligned him with others on the hard right of the party such as Bill Cash and Teresa Gorman.

His voting record as the bill passed through the Commons defined him as one of the more committed of the eurosceptics.

Mr Duncan Smith's instincts are socially conservative: pro-capital punishment, anti-gays in the military and anti-women fighting on the front line.

It was on the latter point that he publicly differed with Mr Hague.

Military mix-up

The Tory leader told a sixth former who wanted to serve in a frontline position with the RAF that he hoped she would "be able to be in the frontline" if she wanted to.

This was an idea that Mr Duncan-Smith has said was political correctness "gone mad".

Hague and Duncan Smith clashed over women in the military

At the time Tory Central Office tried to defuse the split saying: "William Hague fully understands the practical difficulties over women serving in the frontline, and was simply reflecting the aspirations of one girl."

It was not the first time they had clashed.

Threat to resign?

Reputedly Mr Duncan-Smith threatened to resign from the shadow cabinet along with colleague David Heathcoat-Amory if Mr Hague refused to rule out the single currency for a decade.

In any event they remained in the team.

In terms of his prospects as a future leader of the Conservatives he has the difficulty that although he is seen as extremely talented, bright and able he is simply too right wing for many voters to stomach.

Although that remains a matter to be seen.

Popular appeal

There is sufficient confidence of his popular appeal for him to be expected to play a prominent part in the forthcoming election.

In the previous election he had a central role and was even responsible for the New Labour New Danger pamphlet which, along with everything else, failed to stop the landslide.

Mr Duncan Smith is married with four children; his wife Elizabeth is a secretary.

His father was a World War II pilot before he went into business and his mother was a ballet dancer.