Sam Tanenhaus's authorized biography traces William F. Buckley Jr.'s outsized role in shaping modern American conservatism. Beginning with Buckley's privileged upbringing and his Catholic intellectual formation, Tanenhaus follows him through the publication of God and Man at Yale, which announced a young provocateur's arrival, to the founding of National Review, which became the movement's flagship publication. Buckley assembled an improbable coalition of libertarians, traditionalists, and anti-communists, using his personal charm and editorial skill to paper over philosophical tensions. The book examines his complex relationships with figures from Whittaker Chambers to Barry Goldwater to Ronald Reagan, and his efforts to read extremists like the John Birch Society out of respectable conservatism. Tanenhaus brings particular insight to Buckley's contradictions: the champion of free markets who relied on family oil money, the defender of tradition who embraced media celebrity, the intellectual who sometimes valued entertainment over argument. The biography extends through Buckley's later years as his magazine faced financial struggles and his movement transformed in ways he didn't always welcome. This is both the portrait of a singular personality and an essential account of how conservatism became a governing philosophy.