H-022-4: Loss of USS Wahoo (SS-238) and Lieutenant Commander “Mush” Morton
H-Gram 022, Attachment 4
Samuel J. Cox, Director NHHC
On 11 October 1943, the submarine USS Wahoo (SS-238), under the command of the renowned Lieutenant Commander Dudley Walker “Mush” Morton, was sunk with all 79 hands by a sustained air and surface attack as she was attempting to exit the Sea of Japan via La Perouse Strait. At the time, under the aggressive and inspirational leadership of Morton, Wahoo was the most successful submarine in the Pacific. Wahoo’s executive officer on five war patrols was Lieutenant Richard O’Kane, who would go on to be the most successful submarine skipper of the war.
At the time of her loss in October 1943, the Gato-class submarine USS Wahoo (SS-238) was the most storied boat in the fleet. In her seven war patrols, Wahoo would earn six battle stars and a Presidential Unit Citation. The boat would be credited with sinking 20 Japanese ships, 19 of them during her last five war patrols under the command of the legendary Lieutenant Commander Dudley M. “Mush” Morton. During her first five patrols, Wahoo’s executive officer was the equally legendary Lieutenant Richard H. “Dick” O’Kane. (O’Kane would finish the war as a Japanese POW and as the most successful skipper of the war, while his mentor, Mush Morton, would finish third.) Under Morton’s aggressive leadership, Wahoo would be the first submarine to penetrate a Japanese harbor (Wewak, in New Guinea), the first submarine to hit a Japanese destroyer with a “down the throat” torpedo shot, and she sank more ships in less time on her first three patrols under Morton than any other U.S. submarine. Morton would be awarded four Navy Crosses, the last one posthumously. O’Kane would complete five war patrols on Wahoo, and five in command of USS Tang (SS-306), would participate in more successful attacks than any submarine officer in the war, and would be awarded the Medal of Honor, three Navy Crosses, three Silver Stars, and the Legion of Merit with Combat “V.”
In 1995, a private group known as the Wahoo Project began searching for the wreck of the submarine. In 2005, surveys detected a sunken submarine in La Perouse Strait, between the Japanese island of Hokkaido and the Russian island of Sakhalin. In 2006, a Russian team, “Iskra,” surveyed the submarine and conclusively determined that the submarine was not the Soviet L-19 (which had been sunk in La Perouse Strait in 1945, probably by an un-swept Japanese mine after the war was actually over). The Iskra team determined the submarine was Wahoo, a finding that was subsequently verified by the U.S. Navy in October 2006 based on the photographic evidence. The submarine was sitting upright on the bottom, almost entirely intact, and had been sunk by a direct bomb hit near the conning tower.
During the search, extensive Japanese documentation was located, including photos and film of the attack. According to Japanese records, Wahoo was sighted on the surface and fired upon by Japanese shore batteries in daylight on the morning of 11 October 1943. The boat was transiting east, exiting the Sea of Japan, on the day that the pre-mission plan had called for. Wahoo had been under strict radio silence since departing Midway on 13 September, and she was scheduled to break silence once she cleared the Kuril Islands chain, which she never did. Upon being fired upon, Wahoo submerged and possibly struck a Japanese mine and was damaged, because she reversed course to the west back into the Sea of Japan. (It’s also possible she was already damaged, which might explain why she was on the surface in daylight, or that she would have better chance of detecting mines on the surface in daylight.) Regardless, Japanese aircraft sighted a trailing oil slick, tracking Wahoo back to the west.
Between 0945 and 1330, Wahoo was attacked by ten sorties of five aircraft, as well as surface depth charge attacks, before the trailing oil went dead in the water at 1330. Attacks continued until 1630. At least 40 bombs and 69 depth charges were dropped on Wahoo. There were no survivors from Wahoo’s 79-man crew. Wahoo would later be credited with sinking four ships while she was in the Sea of Japan, including the 8,100 ton Konron Maru on 5 October 1943, sunk off west coast of Honshu with the loss of 544 lives, including two Japanese members of the Japanese House of Representatives. The loss of Konron Maru was announced by the Japanese press at the time, and the sinking was a great humiliation to the Japanese navy, which launched a massive operation to hunt down the submarine that caused it. When Wahoo entered La Perouse, Japanese forces were on high alert. With the loss of Wahoo, U.S. submarines did not go into the Sea of Japan again until 1945 when new mine-detection gear was installed.
Wahoo’s Previous War Patrols
First Patrol: Wahoo’s skipper on her first war patrol between August and October 1942 in the general vicinity of Truk Island was Lieutenant Commander Marvin “Pinky” Kennedy and her executive officer was Richard O’Kane. (I don’t know the origin of Kennedy’s nickname, but it may have fit.) The patrol was frustrating due to defective torpedoes, but O’Kane would later say that several missed opportunities were due to Kennedy’s insufficiently aggressive approach. Wahoo was unable to get into firing position for an attack on the seaplane tender Chiyoda (which was being used as a mother ship for midget submarines) and for an attack on an unidentified light carrier (misidentified as Ryujo, which had already been sunk in the Battle of the Eastern Solomons.) Wahoo was credited with sinking one freighter after firing many torpedoes, only one of which exploded.
Second Patrol: Kennedy was still in command for Wahoo’s second war patrol between November and December 1942 in the general vicinity of the Northern Solomon Islands near Bougainville and Buka. Lieutenant Commander Morton was onboard as prospective commanding officer. Morton had, in fact, been relieved of command of the USS Dolphin (SS-169) earlier in 1942 by the squadron commodore due to the boat’s poor material condition, which Morton had maintained was unfixable. Morton’s nickname of “Mush” was actually short for his academy nickname of “Mushmouth,” bestowed apparently because of his propensity for telling tall tales. Relief would have normally ended his career in submarines, but by a fortuitous set of circumstances (one being Kennedy’s lack of aggressive spirit) led to his selection to command of Wahoo. On this patrol, Kennedy claimed to have sunk a freighter and a submarine (misidentified as I-15), neither of which were verified after the war.
Third Patrol: Under the command of Morton, Wahoo got underway from Australia on 19 January 1943, with orders to reconnoiter Wewak Harbor in Japanese-held New Guinea. There were no charts of Wewak, and Wahoo navigated using an Australian school atlas that one of the crewmen had picked up by fluke while in Australia. On 24 January, Wahoo penetrated into Wewak Harbor, sighting the Japanese destroyer Harusame nested with several Ro-type Japanese submarines. Harusame was getting underway, so Morton fired three bow torpedoes at her from 1,200 yards, all of which missed (or failed to function properly). With her position given away by the torpedo wakes, and the Japanese destroyer turning to attack, Morton fired another torpedo, which the Harusame successfully evaded. The destroyer turned to attack again (with Morton reporting that it seemed as if the entire Japanese crew was topside acting as lookouts). Morton waited until the last moment and fired his last bow torpedo (which had been loaded) “down the throat” at the Japanese destroyer. Had the Harusame maintained course, the torpedo probably would have missed, but she turned and caught the torpedo amidships. Harusame beached herself to avoid sinking, and was later re-floated, repaired, and returned to service, which is why Wahoo is not credited with sinking her.
The Buyo Maru Incident: On 26 January 1943, while operating between New Guinea and Palau, Wahoo sighted two Japanese freighters. (Of note, unlike other submarines, executive officer O’Kane manned the periscope during attacks, while skipper Morton analyzed the plots and set up the attacks.) Wahoo fired two bow torpedoes at the lead freighter (Fukuei Maru No. 2) and two at the second smaller unidentified freighter. Two torpedoes hit Fukuei Maru and one hit the other freighter. As Fukuei Maru was sinking, the damaged unidentified freighter turned on a course probably intending to ram Wahoo, but her speed was severely limited. At this point, Wahoo sighted a large transport (Buyo Maru) and a tanker. As the unidentified freighter continued its slow-motion ram attempt, Wahoo fired three torpedoes at Buyo Maru and the second and third hit, which caused Buyo Maru to go dead in the water. Turning to deal with the oncoming unidentified freighter, Wahoo fired two torpedoes down the throat. One hit, but the freighter kept coming, forcing Wahoo to evade. When Wahoo returned to periscope depth, Fukuei Maru had sunk, Buyo Maru was still dead in the water, and the unidentified freighter, having difficulty steering, had joined up with the tanker and was moving away. Wahoo fired another torpedo at Buyo Maru to finish her off. The torpedo passed directly under Buyo Maru and failed to explode. Wahoo fired another torpedo, which was a direct hit, which led Buyo Maru to begin sinking. Morton broke off pursuit of the unidentified freighter and the tanker, figuring he could catch up and deal with them later. After surfacing to recharge his batteries, the submarine returned to Buyo Maru to find many men in the water, and about 20 lifeboats filled with disciplined men in life jackets.
At this point accounts begin to differ about what happened next, with official accounts and other accounts (including some by Wahoo crewmen) differing on who fired first. Morton’s account admits firing on the boats, but not on individuals, and grossly over-estimated the number of Japanese troops lost in the sinking (1,500–6,000 were claimed). O’Kane’s account states that Morton gave the order to fire on a lifeboat to force the Japanese troops to abandon the boats, but that individuals were not targeted and the Japanese returned fire. Vice Admiral Lockwood (COMSUBPAC) reports that the Japanese army troops fired on Wahoo first with machine guns, and that such resistance was not uncommon (and Lockwood was right about that: By that time of the war, Japanese sailors and soldiers would almost always refuse rescue, kill themselves, or resist if they could, sometimes killing U.S. sailors after being brought aboard). All agreed that the soldiers in boats were legitimate targets, since if they reached shore they would resume fighting and kill other Americans. However, author Clay Blair, relying on some accounts by some Wahoo crewmen, states that Wahoo opened fire first and the Japanese returned fire with handguns, and that by some accounts it became a “massacre.” In one account, a man in the water attempted to wave a white flag to no avail, and one man who attempted to board Wahoo was gunned down.
What none of them knew at the time (and what was kept under wraps for over 50 years) was that many of the survivors of the Buyo Maru were Indian soldiers of the 2nd Battalion, 16th Punjab Regiment, who had been captured by the Japanese in Southeast Asia and were being taken to New Guinea as forced labor. There were 1,126 personnel aboard Buyo Maru and 491 of them were Indian POWs. A total of 195 Indians and 87 Japanese (of the 26th Field Ordnance Depot) died in the sinking of Buyo Maru, including the initial torpedo explosions. Most of the Japanese survived the sinking, and were rescued by Japanese ships in the following days, along with more than half of the Indians. (The Japanese would go to great lengths to rescue their own sailors and soldiers, but were less than fastidious with POWs, so how many Indians were killed by the torpedoes, or by Wahoo, or were left behind by the Japanese will likely never be known. That as many survived as did, suggests that the official accounts indicating the firing was somewhat restrained and targeted at boats and not people was true, although there were likely exceptions in the heat of firing, given the hatred that existed toward the Japanese at that time—which was mutual.) Nevertheless, if you search the web for “Wahoo massacre” or “Morton war crime,” you will find quite a raging debate.
Under the Hague Convention of 1907, it was a violation of international law to deliberately kill survivors of shipwrecks, and the statement is pretty unequivocal. Nations were also obligated to rescue and care for survivors (and leaving them in lifeboats was not an acceptable “safe” option), although there was a “so far as military interests permit” clause to rescuing survivors. The “war crime” adherents argue that Morton’s action in sinking the lifeboats and killing at least some of the Japanese survivors was a flagrant violation of international law. Defenders of Morton’s actions (including me), would argue that armed Japanese troops in barges were fair game and were slaughtered by the thousand in the Solomons. Yet, armed Japanese troops in lifeboats, who had a reasonable chance of getting ashore to resume fighting, were somehow to be protected? The Japanese troops aboard the transport were every bit as “defenseless” from the torpedoes as those in the lifeboats were from submarine gunfire. The Japanese themselves would have considered this distinction to be ludicrous, and examples of them machine-gunning U.S. survivors in the water are extensive. By that time in the war, “no quarter,” was not an official policy, but was a fact of life in the war zone, for both sides. The flag flown by Wahoo on her return from her third war patrol probably summed it up: “Shoot the Sunza Bitches.”
As unlikely as it would have been for the United States to have ever charged Morton with a war crime (the U.S. Navy did court-martial a submarine skipper for sinking a hospital ship later in the war, and found him guilty of negligence—he still went on to make flag rank, by the way), the entire U.S. unrestricted warfare campaign against Japan was technically a violation of international law and treaty (and U.S. Navy regulations, for that matter). A follow-on to the 1907 Hague Convention was the Declaration of London in 1909, which stated that submarines were required to abide by the traditional “prize rules” (sometimes called “cruiser rules”) in that civilian merchant ships were not to be sunk unless first warned and crews allowed to abandon ship in an orderly fashion, and were to be taken to a place of safety. On the flip side, merchant ships were not to be armed, and resistance negated the protection of the prize rules. All the Great Powers signed the Declaration of London, but none of them, including the United States, actually ratified it. During World War I, the United States kept insisting that the British and Germans abide by the declaration, to no avail.
After World War I, there was great revulsion against the German’s use of “unrestricted” submarine warfare (which enabled any ship to be sunk without warning) and the U.S. Navy assumed it would never be allowed to conduct unrestricted submarine warfare and therefore did not train for it during the inter-war years. The London Declaration rules were further codified in the London Naval Treaty of 1930 and Article 22 (the Submarine Protocol) of 1936, which required submarines to abide by the traditional prize rules (which wouldn’t do much for the life expectancy of submarines).
In the months leading up to the outbreak of war in the Pacific, senior Navy leaders, particularly CNO Harold Stark, and Chief of War Plans Rear Admiral Richmond Kelly Turner, had resolved among themselves (and with no coordination with the rest of the U.S. government) that upon the outbreak of war with Japan, the U.S. would initiate unrestricted submarine warfare despite the fact U.S. submarines were not trained for the mission. (Neither were Japanese submarines, for that matter.) And, true to expectation, about four hours after the attack on Pearl Harbor, CNO Stark gave the order to execute unrestricted submarine warfare against the Japanese without consulting the rest of the U.S. government, although Stark said he read the contents of the execute message to President Roosevelt before sending the orders and got no objection. For the most part, the view of most senior Navy officers (and most of the country) was that the Japanese “sneak attack” on Pearl Harbor violated the laws of war and forfeited any right to protection under international law. Nevertheless, initial U.S. submarine patrols carried written orders authorizing them to conduct unrestricted submarine warfare, which theoretically would protect the submarine commander from being treated as a pirate by the Japanese in the event of capture—sort of quaint. And as late as 1944, official U.S. Navy regulations still stated that submarines were to abide by the London Treaty. There was actually quite a bit of ambiguity in what was permissible or not in U.S. execution of unrestricted submarine warfare with much left up to the conscience of individual skippers. For example, some skippers would sink Japanese civilian fishing trawlers or junks and sampans with gunfire, while others would refuse to do so.
There is no record that I could find that states that the denial of a Medal of Honor for Morton after the loss of Wahoo was due to the Buyo Maru incident, but it is the subject of speculation and the incident was kept secret for a very long time. Nevertheless, Morton received a Navy Cross for the third war patrol. General MacArthur awarded Morton an Army Distinguished Service Cross for eliminating so many Japanese army troops, and Wahoo received a Presidential Unit Citation.
Meanwhile, the third war patrol wasn’t over. After Buyo Maru was finished off, Morton pursued the tanker and the damaged unidentified freighter and sank both with torpedoes, the freighter being hit by four torpedoes in three attacks before going down. (Of note, Japanese records and post-war analysis indicate only three Japanese ships were sunk in this action, so presumably somehow that tanker survived.)
The fact that Wahoo was out of torpedoes didn’t stop Morton from attacking another convoy. His plan was to surface behind a lagging Japanese tanker, inducing panic and causing the convoy to scatter, which would enable him to sink the tanker with guns. It almost worked, until a Japanese destroyer came charging out of a rain squall, forcing Wahoo to run for it. Wahoo arrived at Pearl Harbor on 7 February after expending all her torpedoes in a 23-day patrol (normal was 60–75 days.) Morton’s example was a huge boost to morale for the U.S. submarine force.
Fourth Patrol: On the sub’s fourth war patrol from February through April 1943, Morton was ordered to take Wahoo into the far northern reaches of the Yellow Sea, near the mouth of the Yalu River, where no U.S. submarine had previously operated. Surprise was complete and the Japanese were unprepared. Wahoo sank numerous cargo ships and freighters, and sank a trawler using home-made Molotov cocktails (a gift from the Marines on Midway). While returning, Wahoo was ordered to the Kurils to intercept a major Japanese effort to defend their garrison on Kiska Island in the Aleutians, which the Japanese aborted after deciding to evacuate the garrison.
Fifth Patrol: Operating in the vicinity of the Kuril Islands between April and May, Wahoo fired ten torpedoes at eight different targets, but faulty torpedoes reduced the number sunk by half. Wahoo hit the seaplane tender Kamikawa Maru, which survived the attack.
Sixth Patrol. Penetrating into the Sea of Japan via the Sea of Okhotsk and La Perouse Strait during August 1943 (without Dick O’Kane on board), this patrol was a total bust due to faulty torpedoes. In her first four days, Wahoo sighted and pursued 12 targets and attacked nine of them, with nothing to show for it. Ten torpedoes definitely broached, had erratic runs, or were duds. Others missed and may have been defective too. This patrol was terminated early.
Seventh (and Last) Patrol: Armed with the new Mark 18 electric torpedo, instead of the Mark 14 steam torpedoes that had proven so unreliable, Morton had lobbied and been given permission to return to the Sea of Japan. According to the plan, Wahoo was to maintain complete radio silence and enter the Sea of Japan via La Perouse Strait on 20 September and transit La Perouse outbound on 11 October She was to transmit after she passed through the Kuril Islands chain.
Of note, one officer who was not aboard Wahoo on this patrol was future intelligence rear admiral and mentor to countless naval intelligence officers (and I was his funeral commander in 2013), Donald “Mac” Showers, whose orders to embark on Wahoo had been cancelled just before departure. As an ensign, Mac was a member of Commander Joe Rochefort’s code-breaking team (as an intelligence analyst, not a code-breaker) in the run up to the Battle of Midway. He would become an intelligence briefer for Admiral Nimitz in the later part of the war. He had volunteered for submarine duty (since all “intelligence officers” at the time were line officers) and was to embark on Wahoo for a “familiarization” ride. With impending operations in Bougainville, Mac’s boss, Commander Jasper Holmes, had Mac’s orders cancelled. The officer whose place Mac was supposed take, Jack Griggs, was already unavailable, and by that fluke survived as well.
For this piece, I consulted numerous sources, particularly trying to find verification of aspects of the Buyo Maru incident. These include the classic The Wake of the Wahoo by Forest J. Sterling (1961) with VADM Lockwood’s foreword, as well as Dudley Morton’s original report, “USS Wahoo (SS-238) 1942–1943—Third War Patrol, January–February 1943.” Silent Victory by Clay Blair (1975, reprint in 2001) was one of the first to offer accounts differing from earlier official accounts, and accounts that Morton fired first. I must offer high praise for Lieutenant Commander Joel Holwitt’s Ohio State University Ph.D. dissertation, “Execute Against Japan,” which is the most comprehensive treatment of the history of unrestricted submarine warfare. (Holwitt also won first prize in the inaugural CNO History Essay Contest in 2017, and second place in 2018.) Other sources included Submarine! by Edward L. “Ned” Beach, (reprinted in 2001 by Naval Institute Press), as well as various accounts by Lockwood and O’Kane.
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