After education at the HMS Conway training school and Royal Military Academy Sandhurst, he served in the Scots Guards from 1975 to 1981, seeing tours in Northern Ireland and Rhodesia.

[1] Following the resignation of William Hague, Duncan Smith won the 2001 Conservative leadership election, partly owing to the support of Margaret Thatcher for his Eurosceptic beliefs.

However, many Conservative MPs came to consider him incapable of winning the next general election and, in 2003, he lost a vote of confidence in his leadership; he immediately resigned and was succeeded by Michael Howard.

He resigned from the cabinet in March 2016, in opposition to Chancellor George Osborne's proposed cuts to disability benefits, returning to the backbenches, where he remains.

[3] He is the son of Wilfrid George Gerald "W. G. G." Duncan Smith, a decorated Royal Air Force flying ace of the Second World War, and Pamela Summers, a ballerina.

[8] Nevertheless, until exposed by the BBC's Newsnight programme, Smith declared on the Conservative Party website and in his Who's Who entry, that he had attended the University of Perugia and the "Dunchurch College of Management".

[8] At the 1987 general election Duncan Smith contested the constituency of Bradford West, where the incumbent Labour Party MP Max Madden retained his seat.

[17] Duncan Smith realised the dangers that he and neighbouring Conservative MPs faced, so redoubled his efforts: "We spent the final week of the campaign working my seat as if it was [were] a marginal.

[21] The 2002 Conservative Party conference saw an attempt to turn Duncan Smith's lack of charisma into a positive attribute, with his much-quoted line, "do not underestimate the determination of a quiet man".

[24] Duncan Smith's 2003 conference speech favoured an aggressive hard-man approach which received several ovations from party members in the hall.

[27] These worries came to a head in October 2003 when journalist Michael Crick revealed he had compiled embarrassing evidence of dubious salary claims Duncan Smith made on behalf of his wife that were paid out of the public purse from September 2001 to December 2002.

[28] Following months of speculation over a leadership challenge, Duncan Smith called upon critics within his party to either gather enough support to trigger a vote of confidence in him or get behind him.

[33] In 2004, Duncan Smith established the Centre for Social Justice, a centre-right think tank working with small charities with the aim of finding innovative policies for tackling poverty.

[39][better source needed] Following the 2010 general election, Duncan Smith was appointed by Prime Minister David Cameron as Secretary of State for Work and Pensions in the Cameron–Clegg coalition.

[55] In the 2012 Cabinet reshuffle, Duncan Smith was offered the job at the Ministry of Justice replacing Kenneth Clarke, but declined, and remained in his post at the DWP.

[61] In May 2014, it was reported the DWP was employing debt collectors to retrieve overpaid benefits, the overpayment purely down to calculation mistakes by HM Revenue and Customs.

[62] After the "workfare" element of the Work Programme was successfully challenged in the courts in 2013, Duncan Smith sought to re-establish the legality of the scheme through retrospective legislation but, in July 2014, the High Court ruled the retrospective nature of the legislation interfered with the "right to a fair trial" under Article 6 of the European Convention on Human Rights.

"[65] In August 2015, Duncan Smith was criticised after the DWP admitted publishing fake testimonies of claimants enjoying their benefits cuts.

[70][71] He later launched an attack on the "government's austerity programme for balancing the books on the backs of the poor and vulnerable", describing this as divisive and "deeply unfair", and adding: "It is in danger of drifting in a direction that divides society rather than unites it.

[78] The honour sparked criticism, with more than 237,000 people signing an online petition, set up by Labour Party activist Dr Mona Kamal Ahmed, a National Health Service psychiatrist, demanding that it be rescinded.

[80] The alliance seeks to "promote a coordinated response between democratic states to challenges posed by the present conduct and future ambitions of the People's Republic of China.

By developing a common set of principles and frameworks that transcend domestic party divisions and international borders, our democracies will be able to keep the rules-based and human rights systems true to their founding purposes.

[87] Following the Liberal Democrats' victory in the North Shropshire by-election, Duncan Smith stated the government had lost focus due to stories about Downing Street parties where COVID-19 rules were broken.

Duncan Smith stated, "The prime minister needs to show really strongly that he doesn't just disapprove but is prepared to get rid of people who are breaking those rules.

"[88] In July 2022, Duncan Smith announced his support for Liz Truss in the July–September 2022 Conservative Party leadership election because she had done more than her opponents to "deliver the benefits of Brexit".

[91] After Tom Tugendhat was chosen as Minister of State for Security, Duncan Smith announced he was considering seeking the Chairmanship of the Foreign Affairs Select Committee.

[92] In September 2022, Duncan Smith joined a number of senior Conservative Party members in calling for the Chinese government's invitation to the Queen's funeral to be withdrawn.

[99] In December 2010, he studied a state-sponsored relationship education programme in Norway, under which couples were forced to "think again" and confront the reality of divorce before formally separating.

The policy has been credited with reversing Norway's trend for rising divorce rates and halting the decline of marriage in the country over the past 15 years.

In a speech delivered in Spain in 2011 he said that only immigrants with "something to offer" should be allowed into the country and that too often foreign workers purporting to be skilled take low-skilled jobs that could be occupied by British school leavers.