Diego with Baltimore (CA-68) and on the 21st escorted President Roosevelt, embarked in the cruiser, north to Adak and Kodiak, Alaska. On 7 August the President shifted to Cummings who got underway for Bremerton in company with Fanning and Dunlap. The destroyer engaged in shore bombardment and other exercises until 17 September when she again steamed for the forward areas. After escorting SS Antigua to Eniwetok, she patrolled with TG 57.7 off Tinian and performed escort duty with TG 30.2 for a diversionary strike against Marcus Island on 9 October. Fanning sortied with TG 38.1 on 16 October to screen a carrier group which launched two strikes against Luzon before moving in to support the Leyte landings. 22 October found the group underway for refueling and replenishment at Ulithi but word of an advancing Japanese fleet caused them to reverse course and the destroyer sped to participate in the action at San Bernardino Strait. After logistics were completed at Ulithi, Fanning moved to Saipan to rejoin TG 30.2 for a series of assaults on Iwo Jima, the first of these on 11–12 November. An assignment as radar picket occupied her until 4 December when she returned to bombard Iwo on the 8th. During the third attack (24 and 27 December) she set a patrol vessel on fire. 1945 In the strike on 5 January 1945 Fanning made contact with a small freighter who tried to ram her and raked her decks before taking a torpedo which sent her to the bottom. Fanning rejoined the group for the bombardment of Chichi Jima, but was soon detached to escort David W. Taylor (DD-551) damaged by a mine, to Ulithi. She returned to the tenacious force once again off Iwo Jima on 24 January and teamed with Dunlap to sink a three ship convoy consisting of transport Yoneyama Maru; and auxiliary minesweepers Showa Maru No. 7 and Keinan Maru. She then assumed station as radar picket and air rescue ship, operating also in local escort duty and in training exercises with a submarine wolfpack through 22 March. The remainder of the war was occupied with patrol and escort activities among the islands of Eniwetok, Iwo Jima, and Guam. On 19 September 1945 Fanning set course for the United States, arriving at Galveston, Texas, on 23 October 1945. Fanning was decommissioned under the command of Commander Earnest "Bud" Conant at Norfolk, Virginia, on 14