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May came to politics early. An only child growing up in rural Oxfordshire in the 1960s, she was inspired not by the anti-establishment spirit of the age, Vietnam War protests, or rebellion in the streets of Paris, but the quiet conservatism of her neighbors. With few close friends to distract her, she joined the Conservative Party and, by the age of 12, had decided to make politics her future.

So deep was her dedication that when her father, Hubert, a Church of England minister, warned her off alienating parishioners who did not share her views, May agreed to confine her activities to stuffing envelopes in a back room. Even the boredom of spending her Saturday afternoons alongside the village matrons in the local Conservative Party office did not deter her.

May met her future husband, Philip, while they were both students at Oxford University, at a dance organized by the student Conservative association. In the 1980s, the two spent the early years of their marriage serving the party in south London, she as a Conservative local councillor and he as an unelected branch secretary. In the 1990s, they traveled the country as she sought to become a member of Parliament. They had few close friends, and both May’s parents had died by the time she was 25. With steady but not particularly inspiring banking careers and, to their deep regret , unable to have children, the Mays made politics the focal point of their life.

Not until 1997 did May finally enter Parliament—as many of her fellow Conservatives were being voted out in favor of Tony Blair’s Labour Party—but it would take another 13 years of slogging in opposition before the Conservatives returned to power. Under David Cameron’s leadership, May reached the highest level of the cabinet, as home secretary.

At the Home Office, May finally received the respect many of those who have worked closely with her say she craves. While the post—which is responsible for a bewildering array of issues from immigration to internet safety, as well as the police—had a reputation of being a political graveyard, May thrived, surviving for six years, the longest run in decades, ending only because she became prime minister.

Many attribute her success as home secretary to an innate pragmatism and a stubborn streak, both boons in a role that requires quick thinking and forceful decision making. She provided strong leadership during a series of terrorist attacks; resisted American pressure to extradite a British national for hacking into the Pentagon, while insisting on it in the case of a radical Islamic preacher accused of terrorist offenses; and oversaw deep cuts to police budgets and staffing numbers.