On this date in history: In 1788, the U.S. Constitution became effective when it was ratified by a ninth state, New Hampshire. In 1942, German forces, led by Gen. Erwin Rommel, took control of Tobruk, Libya, in an assault on British forces. The North African city was a key port on the Mediterranean Sea. In 1945, Japanese defenders of Okinawa surrendered to U.S. troops . In 1964, Ku Klux Klan members killed three civil rights activists -- James Chaney, Andrew Goodman and Michael Schwerner -- and