In that post, she earned the unwanted nickname "Thatcher the milk snatcher" because of her reduction of school milk programs. It was a taste of battles to come.
As prime minister, she sold off one state industry after another: British Telecom, British Gas, Rolls-Royce, British Airways, British Coal, British Steel, the water companies and the electricity distribution system among them. She was proud of her government's role in privatizing some public housing, turning tenants into homeowners.
She ruffled feathers simply by being herself. She had faith — sometimes blind faith — in the clarity of her vision and little use for those of a more cautious mien.
Success in the Falklands War set the stage for a pivotal fight with the National Union of Miners, which began a 51-week strike in March 1984 to oppose the government's plans to close a number of mines.
The miners battled police on picket lines but couldn't beat Thatcher, and returned to work without gaining any concessions.
She survived an audacious 1984 assassination attempt by the Irish Republican Army that nearly succeeded. The IRA detonated a bomb in her hotel in Brighton during a party conference, killing and injuring senior government figures, but leaving the prime minister and her husband unharmed.
Thatcher won a third term in another landslide in 1987, but may have become overconfident.
She trampled over cautionary advice from her own ministers in 1989 and 1990 by imposing a hugely controversial "community charge" tax that was quickly dubbed a "poll tax" by opponents. It was designed to move Britain away from a property tax and instead imposed a flat rate tax on every adult except for retirees and people who were registered unemployed.
That decision may have been a sign that hubris was undermining Thatcher's political acumen. Tens of thousands of protesters took to the streets in London and other cities, leading to some of the worst riots in the British capital for more than a century.