Its not the US but the date of the last well known duel always blows my mind (from Wikipedia):
21 April 1967: The last official duel in the history of France happened between Gaston Defferre and René Ribière, both delegates at the French National Assembly. During an argument in the assembly room, Defferre said to Ribière "shut up, idiot" ("taisez-vous, abruti"). Defferre won the duel after four minutes of sword fighting, wounding his opponent twice.
21 April 1967: The last official duel in the history of France happened between Gaston Defferre and René Ribière, both delegates at the French National Assembly. During an argument in the assembly room, Defferre said to Ribière "shut up, idiot" ("taisez-vous, abruti"). Defferre won the duel after four minutes of sword fighting, wounding his opponent twice.