Answer:
The Pacific Fleet and Admiral were based in Pearl Harbor because it was the primary United States naval base in the Pacific and a critical site for protecting American interests in the region. Pearl Harbor is situated on the Hawaiian island of Oahu, in the midst of the Pacific Ocean, giving it a perfect position for a naval facility. Throughout the nineteenth century, the United States Navy used Pearl Harbor as a coaling and maintenance station, and it grew into a significant naval base in the early twentieth century.
Tensions between the United States and Japan were building in the 1930s, and the United States military understood the significance of securing its Pacific facilities, particularly Pearl Harbor. Admiral Husband Kimmel was named commander of the Pacific Fleet in 1941 and was in charge of the Pacific region's defense. On December 7, 1941, however, the Japanese launched a surprise attack on Pearl Harbor, damaging or destroying many of the United States Navy's ships and planes and killing nearly 2,400 Americans. The strike pushed the United States into World War II, causing a significant shift in US military strategy and operations in the Pacific.