Treaty limits collide with large-carrier doctrine

Aircraft speed, carrier vulnerability, and treaty limits created a linked design problem. Early fighters could launch after visually detecting an incoming strike, but faster 1930s aircraft sharply reduced that margin and strengthened the argument for destroying the enemy carrier first. British operating areas near land bases encouraged greater passive protection, while the wider Pacific favored American emphasis on range, mobility, and strike generation. US doctrine wanted six or eight Lexington-like carriers, but Washington and London treaty cumulative tonnage limits made that impossible. The Midway and Implacable classes were the first carrier generations conceived outside the treaty-era assumptions that shaped Essex and Illustrious. Smaller carriers could multiply decks, yet fixed machinery consumed a larger share of their displacement and they did not efficiently produce the air groups of seventy-two or more aircraft that the Navy sought. Treaties forced procurement compromises even after exercises had clarified the preferred doctrine.