Following promotion to the rank of lieutenant in mid-1941 he was assigned to the battleship USS Oklahoma (BB-37), which was sunk on December 7, 1941, when Japan's surprise attack on Pearl Harbor opened the Pacific War.

In January 1942, Lieutenant Davis was transferred to the light cruiser USS Honolulu (CL-48), in which he participated in operations in the Aleutian Islands, the hard fighting over Guadalcanal and the Central Solomons, and the campaign to recover Guam.

Though horribly burned, Commander Davis remained on his feet, conned the ship, directed damage control efforts and saw to the destruction of the fourth suicide plane.

Walke engaged in a detached mission in support of minesweeping operations to clear the waters for entry of our heavy surface and amphibious forces preparatory to the invasion of Lingayen Gulf, Luzon, Philippine Islands, 6 January 1945.

Seriously wounded when the plane struck, drenched with gasoline and immediately enveloped in flames, he conned the Walke in the midst of the wreckage; he rallied his command to heroic efforts; he exhorted his officers and men to save the ship and, still on his feet, saw the barrage from his guns destroy the fourth suicide bomber.