The contract to build USS Tang was awarded to Mare Island Naval Shipyard on 15 December 1941, and her keel was laid down on 15 January 1943.

[12] Tang completed fitting out at Mare Island and moved south to San Diego for 18 days of training before sailing for Hawaii.

[citation needed] Tang departed Pearl Harbor on 22 January 1944 to begin her first war patrol, destined for the Caroline Islands-Mariana Islands area.

The submarine cleared the area by running deep and then attempted to get ahead of the convoy for a dawn attack, but the remaining freighter passed out of range, protected by aircraft.

[14] She tracked the Japanese ships, through rain squalls which made radar almost useless,[14] for 30 minutes before attaining a firing position, on the surface,[14] 1,500 yd (1,400 m) off the port bow of a freighter.

The escort of the lead ship, the 6,800 ton[15] Yamashimo Maru, moved from its covering position on the port bow, and the submarine slipped into it and fired four more torpedoes.

The first hit the stern of the merchantman, the second just aft of the stack; and the third just forward of the bridge, producing a terrific secondary explosion.

Rain squalls hampered her as she attempted to attain a good firing position, so she tracked the ships until after nightfall, then made a surface attack.

[citation needed] The two remaining ships commenced firing in all directions, and Tang submerged to begin evasive action.

[17][page needed] Additional lookouts had been posted on the target's deck and, when the spread of torpedoes from Tang struck her, they were hurled into the air with other debris from the ship.

[DANFS 1] During this evasion, a water leak developed in the forward torpedo room, and Tang exceeded her depth gauge maximum reading of 612 feet.

She maneuvered into position to attack the wildly zigzagging transport and fired her last four torpedoes and believed she missed; JANAC credited her with sinking Choko Maru, a 1794-ton cargo ship.

[DANFS 1] Tang's second patrol began on 16 March and took her to waters around the Palau Islands, to Davao Gulf, and to the approaches to Truk.

[DANFS 1] On 30 June, while she patrolled the lane from Kyūshū to Dairen, Tang sighted another cargo ship steaming without escort.

A single torpedo blew Nikkin Maru in half, and the transport ship sank, taking with her some 3,200 Japanese soldiers.

However, with rapidly shoaling water and her keel about to touch bottom, Tang drew back, fired a spread of three with two hits, and then surfaced as survivors of the 6,886 ton cargo ship Asukazan Maru were being rescued by fishing boats.

The submarine surfaced and, with the aid of grapnel hooks and Thompson submachine guns, rescued a survivor who had been clinging to an overturned lifeboat.

While prowling the waters off Dairen late the next night, the submarine sighted a cargo ship and, during a submerged attack with her last two torpedoes, sank Dori Maru.

[20] Tang's fourth war patrol was conducted from 31 July – 3 September in Japanese home waters off the coast of Honshū.

On 23 August, the submarine closed in on a large ship; Japanese crewmen dressed in white uniforms could be seen lining its superstructure and the bridge.

A large area stretching northeast from Formosa was known to have been mined by the enemy, and O'Kane was given the choice of making the passage north of the island alone, or joining a coordinated attack group (Silversides, Trigger, and Salmon, under Commander John S. Coye, Jr.,[21] flag in Silversides) which was to patrol off northeast Formosa, and making the passage with them.

The submarine continued on patrol until 23 October, when she contacted a large convoy consisting of three tankers, a transport, a freighter, and numerous escorts.

The tanker struck the transport's starboard quarter shortly after the submarine fired four stern torpedoes along their double length at a range of 400 yd (370 m).

[DANFS 1] As Tang poured on full speed to escape the gunfire directed at her, a destroyer passed around the stern of the transport and headed for the submarine.

The escape was delayed by a Japanese patrol which dropped depth charges, and started an electrical fire in the forward battery.

[26] By the time the last had exited, the heat from the battery fire was so intense, paint on the bulkhead was scorching, melting, and running down.

[30] Those who escaped the submarine were greeted in the morning by the sight of the bow of the transport they sank the previous night sticking straight out of the water.

[31] One of the 78 men lost was Rubin MacNiel Raiford, who at age 15, may have been the youngest American person in the military to lose his life in combat.

O'Kane stated, "When we realized that our clubbing and kickings were being administered by the burned, mutilated survivors of our handiwork, we found we could take it with less prejudice."

[36] Tang has been memorialized as part of a special interactive exhibit at the National World War II Museum in New Orleans, called "Final Mission".