When the Japanese attacked Pearl Harbor, the Pacific Fleet was the most powerful in the US Navy. It was still dominated by battleships, but had been developing naval aviation since the late 1930s and integrating it with the fleet's battleship-led doctrine. This book is the first to examine the Pacific Fleet as it was intended to fight, and how it had been training and preparing in the months leading up to December 7, 1941. Naval historian Mark Lardas explains how, contrary to modern assumptions, the fleet was not wedded to the battleship, but was hedging its bets, building up both its carrier and battleship strength. Most crucially, it had also been developing and honing a massive fleet train, allowing it to operate easily thousands of miles from home. It was this foundation that enabled the Pacific Fleet to adapt so rapidly to the new world of carrier-led naval warfare, and first check and then defeat the Imperial Japanese Navy. With superb artwork, archive photos and 3D diagrams, this is a portrait of the Pacific Fleet during 1941, the last time and place when battleship doctrine held sway.