Thatcher's Trial: Six Months That Defined A Leader by Kwasi Kwarteng, book review: She was never for turning

How a key period in Thatcher's premiership cemented her public image forever

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Kwasi Kwarteng was tipped for early success when he arrived as a newly elected Conservative MP in 2010, but success, in the form of promotion to ministerial office, has so far passed him by. He has, though, become an established voice of the Tory right, and a prolific writer of books. During his first four years in Parliament, he wrote two and co-authored three. He has now added another.

His latest is a narrative account of six months in the life of Margaret Thatcher. According to the book's subtitle, this period between the budget in March 1981 – which Kwarteng accepts was "a Budget to produce three million unemployed" – and the reshuffle in September, when she sacked three Cabinet ministers and the party chairman to bring on the Thatcherites Nigel Lawson, Cecil Parkinson and Norman Tebbit – "defined" her as a leader. Between those dates, the Labour Party was torn in two, bringing the short-lived Social Democratic Party into existence, the IRA's first elected MP, Bobby Sands, starved himself to death in H-block prison, and riots erupted in Brixton, Toxteth and other city centres. (There was also a royal wedding, of Prince Charles and Lady Diana Spencer, which probably drew more public attention than all the other events combined, but Kwarteng lets that pass in a single sentence).

Given who Kwarteng is, there are no prizes for deducing where his sympathies lie. He, of course, admires Thatcher as one who "fought passionately for absolute values in a world which seemed diffident and uncertain of purpose." But enough time has passed since her departure for those who belong to a tradition that used to gaze upon the lady in a spirit of swivel-eyed sycophancy to study her record with some detachment.

While Kwarteng's book is no match for Charles Moore's monumental biography, it is well written. To avoid the trap of being wise a generation after the events, he has relied throughout on contemporary documents, memoirs and newspapers to form a clear idea of how Margaret Thatcher was seen in 1981. There is a revisionist view of Thatcher's premiership, advocated by the historian of post-war Britain, Norman Sandbrook, among others, which says that Thatcher was not necessarily the ideologically driven "Iron Lady" of popular imagination but a pragmatic operator who knew when to retreat – as when her government abandoned the threat of pit closures early in 1981 to avert a miners' strike.

Kwasi Kwarteng will have none of that. He is in no doubt that Margaret Thatcher was driven by a black-and- white belief in right and wrong imbued during her Methodist upbringing, and by a perpetual belief that there was an "enemy within". Other biographers have suggested that she turned her back on that upbringing when she married Denis Thatcher, a rich, divorced Anglican, but Kwarteng is sure that non-conformist Christianity and her university training as a scientist pervaded what he calls her "rather plodding, even if fastidiously accurate, fact-based mental processes".

She cited the Bible so often and with such confidence that, he amusingly notes, she did not feel she needed to have anyone check for her to ensure she was doing so accurately. As a result "few misquoted the King James Bible more frequently than Margaret Thatcher".

He demonstrates that the phrases most commonly used about her – the "Iron Lady", the comparison with Boudicca, and Tina, acronym for "There is no Alternative" – were all in circulation when Thatcherites were still a minority within her own Cabinet. "The striking thing about Margaret Thatcher," he concludes, "was how little, in fact, she developed from her assumption of the Tory leadership in 1975 to her last days in Number 10 in 1990."

Even now, Margaret Thatcher is a divisive figure. Those who want to read only about the evil she did should, I suppose, avoid this study. For others, it is an easy read that does not lecture: it tells.