 The two Shōkaku @-@ class ( <unk> , Shōkaku @-@ gata ) aircraft carriers were built for the Imperial Japanese Navy ( IJN ) in the late 1930s . Completed shortly before the start of the Pacific War in 1941 , they have been called " arguably the best aircraft carriers in the world " when built . With the exception of the Battle of Midway , they participated in every major naval action of the Pacific War , including the attack on Pearl Harbor , the Indian Ocean Raid , the Battle of the Coral Sea , and the Guadalcanal Campaign . 
