 The plan was handicapped by faulty Japanese assumptions of the American reaction and poor initial dispositions . Most significantly , American codebreakers were able to determine the date and location of the planned attack , enabling the forewarned U.S. Navy to prepare its own ambush . All four of Japan 's large aircraft carriers — Akagi , Kaga , Soryu and Hiryu , part of the six @-@ carrier force that had attacked Pearl Harbor six months earlier — and a heavy cruiser were sunk , while the U.S. lost only the carrier Yorktown and a destroyer . After Midway and the exhausting attrition of the Solomon Islands campaign , Japan 's capacity to replace its losses in materiel ( particularly aircraft carriers ) and men ( especially well @-@ trained pilots and maintenance crewmen ) rapidly became insufficient to cope with mounting casualties , while the United States ' massive industrial and training capabilities made losses far easier to replace . The Battle of Midway is considered a turning point in the Pacific War . 
