Historian Rick Perlstein traces the country's ideological divisions from John F. Kennedy's assassination through Richard Nixon's campaign to modern politics.

Political scientist Lori Cox Han traces the growing role of women in politics from 1968 to now: "Women are not a monolithic voting bloc, and I think that's one of the biggest misconceptions out there."

Roger Ailes helped Republicans use television to get elected for decades. He was more politically influential than many politicians themselves. In 1968, Ailes helped Richard Nixon win the White House -- and he was only getting started. Gabriel Sherman, author of a biography on Ailes, traces how...