Few political leaders have the honour of getting an ideology named after them. But Thatcherism has defined Britain, for better or worse, for the decades during and since her premiership.
Margaret Thatcher was the woman who, virtually single-handed and in the space of one tumultuous decade, transformed a nation.
Her supporters believe she put the drive back into the British people. Her detractors, just as vociferous, saw her as the personification of the uncaring new political philosophy.
A 1980 file photo showing British Prime Minister Margaret Thatcher
Tireless, fearless, unshakeable and always in command, she was Britain's first woman Prime Minister - and the first leader to win three General Elections in a row.
Her fall from grace came in 1990, a year in which she faced a series of damaging resignations from the Cabinet, her own political judgments were publicly denounced by her own colleagues, catastrophic by-election humiliations, internal party strife, and a sense in the country that people had had enough of her after 11 years in power.
But history will almost certainly proclaim her as one of the greatest British peacetime leaders.
And as she transformed the nation - attempting to release the grip of the state on massive industries and public services alike - she strode the earth as one of the most influential, talked-about, listened-to and dominant statesmen of the Western world.
When Argentina invaded the Falklands, she despatched a task force to the South Atlantic which drove the enemy off the islands in an incomparable military operation 8,000 miles from home.
She successfully defied Arthur Scargill's nationwide and year-long miners' strike, which threatened to cripple Britain's entire economic base.
Her triumphant achievement of power in May 1979 signalled the end of the era when trade union leaders trooped in and out of 10, Downing Street, haggling and bargaining with her Labour predecessors.
Instead she stripped the unions of many of their powers with the aim of transferring them to managements and individual consumers.
Within weeks of her arrival in Downing Street, foreign correspondents from all points of the globe - absent for so long from the House of Commons - flocked back to the press gallery.
It was a sure sign that the world was sitting up and listening once again to what Britain had to say.
Whether you liked Mrs Thatcher or loathed her - and her Tory predecessor Edward Heath hated her beyond belief - whether you agreed with her or found her policies utterly repugnant, you could not deny her energy and drive.
Even many political foes secretly admired this single-minded woman, who never contemplated defeat and for whom all issues were black and white, not hedged about with grey.
Even - indeed particularly - her most bitter political enemies were forced to praise her crusading clarity of purpose and her determination, in their eyes, to serve "her people".
Veteran left winger Tony Benn frequently held her up as an example of how a great political party should be led, comparing her with what he regarded as Neil Kinnock's fudged leadership of the Labour Party.
Margaret Thatcher towered above all other political figures in Britain and her dominance of the Cabinet was supreme and rarely challenged. She was the equal of statesmen across the world. She elevated Downing Street to something like the status of the White House and the Kremlin, symbols of the then two great superpowers. Nobody talked down to her.
Denis Thatcher, his wife former Prime Minister Baroness Thatcher, and Prime Minister Tony Blair
Yet the Iron Lady - a title bestowed upon her by her enemies in Moscow, which, incidentally she relished - was not all stern, steely and strident. She was delightful with children and she could not disguise her glee - "We are a grandmother" - when her grandson Michael was born in Dallas in February, 1989.
She regularly and touchingly admitted that she could not do her job properly without the unfailing and unstinting support of her "marvellous" husband, Denis. He was, she said, the "golden thread" running through her life.
His death, in June 2003, some weeks after major heart surgery, was a profound blow to her.
Sir Denis, as he became after she left Downing Street, was constantly at her side, an impeccable consort, protecting her and guiding her in all weathers and in all parts of the world.
He was a wonderful source of encouragement and comfort to her when, as sometimes happened, she returned home in tears after a particularly gruelling day. He made no attempt to disguise his contempt for those who opposed his wife, but he never got involved publicly in policy or political discussions.
His death came at a time when Margaret Thatcher's own health - she was ten years younger than him - was the subject of speculation. She had suffered a series of strokes and her doctors had forbidden her to make any more speeches - instructions which she was occasionally known to breach.
Sir Denis's death was a massive blow to Lady Thatcher. But there was more grim trouble ahead.
Her son, Sir Mark - he inherited the baronetcy from his father - was charged in South Africa in connection with a plot to overthrow the Government of oil-rich Equatorial Guinea. The charge carried a maximum penalty of 15 years, and possible death if Sir Mark was extradited to Equatorial Guinea.
The news broke when Lady Thatcher was on holiday in the United States. She doted on her son and the charge plainly devastated her.
However, after weeks under house arrest in Capetown, where he lived, Mark in January 2005, pleaded guilty to unwittingly helping to finance a foiled coup plot in oil-rich Equatorial Guinea. He accepted a three million rand fine and a suspended jail sentence.
Thatcher always conceded that personal attacks on her, and particularly on members of her family, wounded her deeply.
And yet the woman who took on Argentina and who had the people of Moscow reaching out and yearning to touch her, could not bear the sight of creepy-crawlies or snakes.
Mrs Thatcher was obsessively British, batting for Britain wherever she went, wearing exquisite home-produced clothes, upbraiding those who did not, and turning up her nose at the French Perrier Water. "What's wrong with British water?" she demanded.
Her dramatic downfall came about during the second of two challenges to her leadership. She realised that if she stayed on to take her challenger Michael Heseltine - a man she disliked intensely, personally and politically - into a second ballot, he would almost certainly supplant her. That was a prospect she could not bear to see happen.
And so, after consulting her Cabinet colleagues, one by one, she decided she must go, and tearfully gave the Cabinet the news the following morning.
By doing so, she paved the way for one of her favourite "sons" John Major to follow her into 10, Downing Street.
But her support for him was luke-warm. She was to say later that she backed him because he was "the best of a poor bunch".