AD 68 - Nero commits suicide, after quoting Homer's Iliad, thus ending the Julio-Claudian dynasty and starting the civil war known as the Year of Four Emperors (Source)
More recommended sermons and podcasts: Nero Leads Ireland, Belgium, Colorado - Top Moral Cesspools in the World, by Pastor Kevin Swanson
1954 - McCarthyism: Joseph Welch, special counsel for the United States Army, lashes out at Senator Joseph McCarthy during hearings on whether Communism has infiltrated the Army giving McCarthy the famous rebuke, 'You've done enough Have you no sense of decency, sir, at long last? Have you left no sense of decency?" (Source)
Recommended reading: On Joe McCarthy, the Washington Post Gets It Embarrassingly Wrong - lewrockwell.com