Yamamoto thought that the Americans had been demoralized by their defeats in the last six months. He thought a trick would lure the U.S. fleet into a dangerous situation. He spread out his ships, especially his battleships, so that they would be hard to find. Yamamoto's battleships and cruisers went behind Vice-Admiral Chūichi Nagumo's carrier force by several hundred miles. Japan's heavy surface forces would wait for the U.S. ships to come to defend Midway, and destroy them.