Hart conducted her regular shakedown cruise off
California and during her training participated in experimental high-speed refueling exercises with . From 12 to 23 December, the destroyer refueled at sea some 50 times under all conditions of sea and weather gaining vital information on how to improve this key wartime operation. Ending her regular shakedown on 31 January 1945, the ship departed on 19 February for
Pearl Harbor. From 27 February to 3 March she escorted in gunnery and aircraft operations, departing for
Ulithi on 5 March. Arriving at Ulithi 16 March,
Hart joined the assembled task forces for the
Okinawa operation. From 24 March to 12 April, the ship was assigned as part of the screen for
escort carriers furnishing
close air support for the landings and preinvasion neutralization of neighboring
Japanese air strips. Detached on 12 April, she assumed duty as an escort for transports for 2 days and then commenced protective patrol duties during landings near
Okinawa.
Hart was detached from
5th Fleet on 19 April and proceeded to the
Philippines to join
7th Fleet for the
Borneo landings. She arrived off
Brunei Bay on 9 June 1945 and commenced a patrol of the
South China Sea to guard against possible interference from the remains of the Japanese Fleet at
Singapore.
Hart also carried out shore bombardment beginning 11 June in support of
Australian troops landing at Brunei Bay. On 14 June, she shot down her first Japanese aircraft during an attempted bombing. During the period of 19–21 June, she provided close support for further landings on the coast of Borneo near Brunei Bay, and then departed for
Balikpapan and other amphibious operations. While there,
Hart patrolled, provided
star shell illumination, and directed
minesweeping vessels through the treacherous enemy
minefields off the beaches. Australian troops went ashore on 1 July, under cover of fire from
Hart and other ships; during the operation
Hart destroyed two mines and a 75 mm gun emplacement ashore. Temporarily leaving the landing areas,
Hart was assigned as part of the escort for
Major General Douglas MacArthur in , steaming to
Manila with the General and then proceeding to
Leyte on 5 July. She next moved to
Subic Bay for training exercises and escort duty, and after the surrender of
Japan on 15 August was assigned to the newly formed
North China Force.
Hart departed on 5 September 1945 to support the landing of
Army occupation forces at
Jinsen,
Korea. The force threaded its way through many mines en route, and after arrival,
Hart sent boarding parties on board Japanese merchantmen in the harbor for inspection and disarming. This duty completed,
Hart sailed for
China, escorting Cruiser Division 6 in an important show of force off the coast. She continued through the next few months to aid in the landings of
American Marines, calling at
Port Arthur,
Tsingtao, and
Taku. The veteran destroyer sailed for the United States 9 February 1946, decommissioned 31 May 1946, and was placed in reserve at
Long Beach, California. She was later moved to
Mare Island Naval Shipyard, and then
Stockton, California.
Hart was stricken from the
Naval Vessel Register 15 April 1973, was sold on 3 December 1973, and broken up for scrap. ==Awards==