Contrary to a common misconception, the U.S. Pacific Fleet headquarters was not "moved" from the West Coast to Hawaii—it has been based at Pearl Harbor since the early 20th century.
Today, the fleet's headquarters is located at Joint Base Pearl Harbor–Hickam on Oahu. The West Coast (particularly San Diego) remains home to the U.S. Third Fleet and major naval installations, but the Pacific Fleet's command has long been centered in Hawaii due to its strategic mid-Pacific position.
So, there was no relocation; Hawaii has been the Pacific Fleet's home for over a century.