During the Washington Conference of 1920, the Americans took a hard look at their Navy. They had a Navy second only to the British, and like the Royal Navy, they had to protect interests in two oceans. Yet voluntarily they gave up building several ships and scrapped others. Unlike the Japanese and German Navies, they would hold themselves to the Treaties and build ships that would be outclassed just a few years later by their Axis counterparts.
Just twenty-five years later, the US Navy would field thousands of ships and aircraft over Tokyo Bay. The transformation would occur within four years; most of the ships in Tokyo Bay were not even on the drawing table in 1940. The creation of a purpose-built amphibious fleet was an industrial miracle. Most of the specialized designs were British inventions built in American yards.
Two men were most responsible for engineering the mass construction. Henry Kaiser, who invented new ways to build cargo ships, started building ships faster than the Axis could sink them, ensuring that the supplies could get through. Andrew J. Higgins built a new kind of landing craft that could drop its front ramp, allowing easy disembarkation. Many different types of these boats would be built for the US Navy. Mastering the ability to supply operations from the sea was a technique the Axis never matched, and it provided a powerful weapon to the Allied cause.
With the losses at Pearl Harbor, the US Navy under Nimitz was forced to undertake a whole tactical doctrine. Since the invention of gunpowder, ships had been essentially floating gun platforms. With the US carriers the only capital ships left in early 1942, they were the only units able to bring the fight to the enemy.