I-175 began life as I-75, laid down at the Mitsubishi shipyard in Kobe on November 1, 1934, and commissioned on December 18, 1938. She was a Kaidai-type cruiser submarine of the KD6B subclass -- 105 meters long, displacing 1,785 tons on the surface, capable of 23 knots above water and 8 knots below. Her surface range of 10,000 nautical miles at 16 knots made her an ideal long-range raider. In October 1940, she joined 97 other warships and more than 500 aircraft at Yokohama Bay for the largest fleet review in Japanese history, celebrating the 2,600th anniversary of Emperor Jimmu's legendary enthronement. Fourteen months later, she was at sea heading for Hawaiʻi, assigned to support Operation Z -- the attack on Pearl Harbor.

I-175's war was a tour of the Pacific's bloodiest campaigns. She provided weather reports southwest of Oahu during the Pearl Harbor attack, served at Midway, and operated in the Guadalcanal campaign. By 1943, she was running supplies to beleaguered Japanese garrisons in the Aleutian Islands -- unglamorous but essential work. She hauled ammunition and food to Kiska, evacuating soldiers in batches of sixty and seventy at a time. When U.S. forces landed on Attu in May 1943, I-175 was ordered south of Kiska to support a counter-landing that never materialized, because the Japanese garrison on Attu was annihilated before reinforcements could arrive. After a fruitless eighth war patrol hunting Allied shipping near Amchitka, she returned to Kure, Japan, in August 1943.

The sinking of Liscome Bay was not a planned attack but an opportunistic strike during chaos. I-175 was returning to Truk when the U.S. offensive in the Gilbert Islands began on November 20, 1943. Ordered to Butaritari at flank speed, she arrived as American forces were withdrawing after capturing the atoll. At dawn on November 24, the battleship USS New Mexico detected her on radar twenty nautical miles out. I-175 submerged, avoided the initial response, and closed the distance. She fired four torpedoes at the task force. Two missed. One struck Liscome Bay's starboard side aft of the engine room. The bomb magazine erupted, and the carrier's stern disintegrated. Among the 644 lost when the ship sank were Rear Admiral Henry M. Mullinnix, Captain Irving D. Wiltsie, and Doris Miller -- whose heroism at Pearl Harbor had made him one of the most celebrated sailors in the Navy. Only 272 men survived.

I-175 survived a six-hour counterattack after sinking Liscome Bay. Two destroyers dropped thirty-four depth charges, six of which detonated close aboard. She surfaced days later to report that the blasts had limited her diving depth, a wound she carried for the rest of her operational life. After refueling overnight at Kwajalein, she limped to Truk. Her commanding officer received a personal commendation from Vice Admiral Takeo Takagi for the sinking. But I-175's reprieve was measured in weeks, not months.

On January 27, 1944, I-175 departed Truk for her tenth and final war patrol, heading northeast of the Marshall Islands with the commander of Submarine Division 12 aboard. The U.S. invasion of Kwajalein began while she was at sea, and she was redirected to reconnoiter Wotje Atoll. On the night of February 3, a U.S. battleship detected a vessel on radar east of Wotje. The destroyer USS Charrette closed in. At 10,300 yards, the radar contact disappeared -- a submarine diving. Charrette achieved sonar contact and dropped eight depth charges. The destroyer escort USS Fair fired ten Hedgehog projectiles. Four explosions confirmed the kill, roughly 100 nautical miles northwest of Jaluit Atoll. On March 26, 1944, the Imperial Japanese Navy declared I-175 presumed lost with all 100 hands. She was struck from the Navy List on July 10, 1944. Her wreck lies somewhere on the floor of the central Pacific, unmarked and unrecovered.