Margaret Thatcher was leader of the Conservative party for almost sixteen years and Prime Minister for eleven years. Under her leadership the Conservatives won three general elections and re-established themselves as the dominant party in the British state, while Labour declined to its interwar level of support. It was a period of almost unbroken Conservative success, which followed a period when the Conservatives had appeared to be in decline, and in danger of ceding their claim to be the natural party of government to Labour.

Thatcher’s style of leadership was closely associated with that success. From the outset a cult developed around her, fostered by her ability to outlast and outfight all opponents. Even when she was finally ousted in the leadership election in 1990—following the extraordinary poll tax fiasco, the resignation from her Cabinet in the space of twelve months of two of the key architects of Thatcherism, Lawson and Howe, after major policy disagreements, and the collapse of her standing and that of the government in the polls—she still won fifty two more votes than her challenger, Michael Heseltine. Only the curious rules which the Conservatives had adopted in the 1960s denied her victory on the first ballot and then only by four votes. Her decision not to stand in the second ballot, after several members of her Cabinet had advised her that she could not win, ended her leadership, but allowed her to claim that she had never lost an election.

During her period as Prime Minister she came to dominate British politics in a manner which has rarely been equalled. Yet she came to the leadership by accident in 1974, aided by the turmoil of the time, and on several occasions before 1990—the 1981 slump, the Falklands War, and the Westland Affair—her position was in danger. But she always survived. She constantly denied suggestions that she might retire voluntarily from the leadership. In 1989 her supporters chanted ‘Ten More Years’ at the Conservative Party Conference, and she kept telling interviewers how much more there was to be done.

Her legacy is deeply contentious, nowhere more than in the Conservative party itself. While she was leader she received greater adulation from Conservative party members and Conservative newspapers than any Conservative leader since Churchill, and inspired enormous devotion and enthusiasm in a section of the parliamentary party. Yet in other parts of the party she excited deep hostility. She polarized the Conservative party in a manner which was exceptional in its modern history. The Conservatives have had many divisions over particular issues—such as Tariff Reform, India, Suez, Rhodesia, immigration, and the ec. But the divisions have rarely lasted, in part because the leadership has normally attempted to minimize the conflict and to mediate between different strands of opinion in the party.

Under Thatcher many of the conflicts and divisions in the Conservative party stemmed directly from the style of her leadership. Her dislike of having internal arguments, her scorn for consensus, her description of herself as a conviction politician, her desire to know whether someone was ‘one of us’, soon marked her out as an exceptionally forceful leader who obliged everyone to define themselves as either an enemy or friend. She left no middle ground.