70 Years Ago—Dec. 10, 1941: British enter Tobruk, Libya, relieving 242-day German siege. First US bombing mission of war, as B-17s of the 19th Bomb Group attack Japanese ships off Luzon in the Philippines. British Prince of Wales and Repulse sunk off Malaya by Japanese aircraft; 730 killed—first time in history that battleships are sunk by planes.