Because of the slow communications of the day, word of peace had not reached New York by 15 January 1815 when the frigate USS President, commanded by Captain Decatur and having Hamilton as one of her lieutenants, ran the blockade out of that port.

Wartime duties now took Hamilton on coastal convoys from New York through German U-boat-infested waters as far south as the Panama Canal Zone.

The shifting tide of war drew Hamilton from the coastal convoy route in the fall of 1942 as she became part of "Operation Torch," the Allied invasion of North Africa.

Hamilton sailed for North Africa on 24 October with Rear Admiral H. K. Hewitt's Task Force 34, a part of the Allied amphibious thrust.

Two weeks later, she cruised off the Moroccan coast providing antisubmarine (ASW) protection and fire support for the first waves of invasion barges as the Allies landed at Casablanca, Oran, and Algiers on 8 November 1942.

The following year saw Hamilton engaged primarily in coastal convoy duty, guiding and protecting merchantmen as they threaded their perilous way through German submarine packs from Iceland to the Caribbean.

As the Marines stormed ashore there on 31 January 1944, Hamilton steamed in the area to screen transports and provide the fire support that made it possible to land and stay.

At Nouméa, Hamilton joined forces with three other destroyers converted to fast minesweepers-Hovey, Long, and Palmer—to form a preliminary sweep unit.

It was the mission of these ships to enter enemy harbors three to five days before landings to clear out mines and provide safe anchorage for the invasion force.

The day organized enemy resistance on Saipan ended, Hamilton sailed from Eniwetok on 9 July to take part in the preliminary bombardment and sweeping activities at Guam.

For destroying three extensive minefields, which the Japanese had hoped would ward off or severely damage the invasion force, Hamilton and the other minesweepers received the Navy Unit Commendation.

Three days before Army divisions came ashore, Hamilton swept the channels around Diriagat Island and Looc Bay to clear the way to the invasion beaches.

Arriving at Manus, Admiralty Islands on 31 October, Hamilton underwent availability and repairs and, once more ready for battle, sailed on 23 December to prepare the way for the invasion of Lingayen Gulf.

After the invasion forces landed at Lingayen Gulf on 9 January, Hamilton remained as a transport screen and escort until 1 February when she sailed for Saipan.

Hamilton reached Pearl Harbor via Eniwetok on 25 March 1945 and, after a brief period of training, headed back to the continental United States.

The ship spent the few remaining months of the war participating in experimental minesweeping work along the California coast out of Santa Barbara.