"I am a conviction politician," British Prime Minister Margaret Thatcher boldly declared in 1979, and her expressive stand against consensus politics won immediate endorsement from Ronald Reagan. Both promised to provide strong leadership, establish new priorities, and restore fundamental principles to national politics. To many they appeared to form a transatlantic partnership, but they were not the first.

Looking back over 200 years of history, Patricia Lee Sykes examines presidents and prime ministers to show how idealistic leaders have challenged liberal ideas and institutions within...