During forty-four months of participation in World War II, the Empire of Japan suffered the loss of 2,346 merchant ships. Virtually all of her vessels of 1,000 tons and larger were either sunk or rendered inoperative. The lost ships represented a staggering total of 8,618,109 gross tons.
Linked directly with the disappearance of her merchant fleet, Japan also lost 686 ships built for her Imperial Navy. When the occupying forces of the victorious Allies moved into the home islands in September of 1945, they found the floating equipment of a seagoing nation reduced to little more than a fleet of fishing craft. Such obliteration of a great sea power is without parallel in the annals of maritime history.
In the years immediately preceding the attack on Pearl Harbor, Japan’s merchant shipping program had amazed the world. Between two World Wars her shipyards had hummed with activity. Vessels flying the flag of the Rising Sun moved into nearly all important trade routes. By 1939 the Japanese were firmly in third place among the world maritime powers. Their ships held a dominating position in transpacific passenger and cargo services. Their modern diesel-engined liners and cargo ships had invaded the major ports of every continent in all the hemispheres. They were operating on regular schedules into New York and to London and the seaports of western Europe. Their entry into an around-the-world service, with definitely fixed dates of sailing, had proved successful. And they had built the world’s first fleet of high-speed, 100,000-barrel capacity oil-tankers.
All this had been accomplished by a nation which controlled very little of the world production of essential shipbuilding and ship operating materials. From abroad, the Empire was forced to buy its iron, manganese, chromium, aluminum, copper, petroleum, rubber, and many other basic and strategic supplies.
Prior to the great wave of nationalism in shipping, Japan had purchased many of her deep sea vessels in Europe and America. For years many of these ships had to be entrusted to foreign officers. As late as 1925 the author of this article was on board a large Japanese transpacific liner which had been bought secondhand in San Francisco and which then operated under a master, chief engineer, and chief radio operator who were all British subjects. But by the middle 1920’s, Japanese training schools were turning out licensed and unlicensed crew personnel by the thousands, and the ships of Nippon were soon wholly manned by Japanese nationals, as well as being the products of Japanese shipyards.
Japan’s centralized control of industry, a governmental plan for financing overseas purchasing, the ability of her designers to copy and adapt the best features of foreign naval architecture, and the comparatively low living and wage standards of those who manned her merchant marine, helped this great program of sea power expansion.
By September of 1939 the Empire had in service—according to the Maritime Commission of the U. S. Department of Commerce —1,180 vessels, each of 1,000 gross tons or more. Only the British Empire and the United States had larger merchant fleets. And Japanese shipyards had not yet reached the high peak of wartime production which was soon to follow.
With the attack at Pearl Harbor on December 7, 1941, the Japanese merchant marine was ready for an almost overnight conversion into a war fleet. Large liners became transports and tenders for seaplanes, submarines, and destroyers. Freighters and “silk express” ships became troop and cargo carriers. Tankers became fuel ships for the Imperial Navy and for the air units. The larger fisheries trawlers had been designed for quick transfer into navy mine and net layer duties.
Because her entry into the war had been carefully timed, Japan had all of her merchant ships in home ports or nearby waters. Unlike Germany and Italy, none of her tonnage was lost to enemy blockades or through internment in neutral harbors.
As the great Pacific war of 1941-45 progressed, Japan launched new ships by the hundreds. And soon her enemies, principally the United States, began to destroy them by the hundreds. Of all Japanese losses at sea, both merchant and navy vessels, 54.6 per cent were sunk by United States submarines. Of the 2,346 merchant ships destroyed, 2,119 were the victims of either the Navy or the Air Force of the United States. America’s allies accounted for 227 destroyed merchantmen.
While all of the sinkings were damaging blows to the Empire’s war effort, some were incidents of spectacular or special significance. Many of these incidents have been described in several books written on United States submarine warfare and air activities in the Pacific.
The Japanese “big three” before the war had been the N.Y.K. Line’s prize transpacific motor liners. Their speed of 21 knots and their size made them very valuable transports, and they managed to survive thousands of miles and many months of wartime service. But in the end they fell prey, one at a time, to United States submarines patroling the western Pacific.
Beginning with her maiden voyage in 1930 to Honolulu, San Francisco, and Los Angeles, the Tatsuta Maru, 16,979 gross tons, operated on a rigid schedule through eleven peacetime years. She became a favorite with tourists and commercial travellers alike, and her popular, golf-playing master, Captain Shunji Ito, acquired a veritable host of friends in many countries. And it was this ship which sailed out of the Golden Gate on August 4, 1941, to mark the last appearance of a Japanese merchant vessel in an American port until after the war.
The final voyage of the Tatsuta Maru came fourteen months after Pearl Harbor, when she was ordered to carry a full load of troops and war cargo to the great mid-Pacific base area centering on Truk. During the night of February 8, 1943, and 200 miles from Yokohama, she became a perfect target for the USS Tarpon. The submarine first made radar contact at 10,000 yards, then closed to 1,500 yards, and fired. Vice Admiral Charles A. Lockwood, U. S. Navy (Retired), wrote in his book, Sink ’Em All:
“Tarpon had the most satisfying experience that a submarine can enjoy—four shots, four hits, target sunk.”
The transport was heavily escorted at the time and severe and prolonged depth charges followed the attack, but the Tarpon escaped “without suffering any damage except nerves.”
Captain Ito was not on board when the end came, and in 1947 he died in Japan, a tired little man of the sea with a deep sorrow over the loss of a famous ship which he had commanded on scores of voyages between the Orient and California.
The Kamakura Maru, 17,526 tons, had been Japan’s largest passenger ship. She was the newest of the “big three,” and the Emperor and members of his household were reported to have once made an unprecedented inspection tour aboard. The able and dignified Captain Y. Arakida was master of the liner through most of her ten years of peactime service.
In the spring of 1943 the transport Kamakura Maru came to her final and fateful voyage. With her holds and ’tween decks filled to capacity with troops and cargo, and with her cabins occupied by 1,000 civilian engineers and technicians, she was routed south with Singapore as her destination. The civilians had been assigned to step up production of rubber, petroleum, and other critical materials in Malaya and the captured islands of the Netherlands East Indies.
On April 28, 1943, in the South China Sea, torpedoes from the USS Gudgeon found their mark. Only 28 of the civilians survived. This was a major blow, for Japan had no replacements for either her engineers and technicians or for her largest military transport.
The Asama Maru, an identical sistership of the Tatsuta Maru, had likewise seen ten years of highly profitable peacetime service for the N.Y.K. Line. She, too, had become a popular passenger carrier under command of the genial Captain T. Watanabe. On one of her eastbound voyages she carried the Japanese, Thailand, and East India teams to the 1932 Olympic Games in Los Angeles. And before Japan’s entry into the war, the Royal Navy had once forced the Asama Maru to stop in the Pacific for the purpose of removing 21 German passengers who had been crew members of the scuttled pocket battleship Graf Spee.
The Asama Maru survived almost three years of warfare before American submarine torpedoes sent her down on November 1, 1944 near the southern end of Formosa. The “big three” had all been accounted for.
On December 22, 1944, the USS Flasher scored a telling blow off the coast of Indochina. Attacking a convoy, the submarine sank three large tankers—the Arita Maru and the former Mitsui Line sisterships Otowasan Maru and Omurosan Maru.
The Empire lost-all of her large whale oil factory ships. Tonan Maru No. 2, with 19,262 gross tons, went down in the East China Sea when struck by torpedoes from the USS Pintado. U. S. Navy carrier planes bombed and sunk Tonan Maru No. 3 while operating among the Caroline Islands. One of the newer vessels of this type, Kyokuyo Maru, 17,548 tons, was last heard from in the East China Sea on November 13, 1943. The cause of her disappearance could not be definitely determined by the post-war Joint U. S. Army-Navy Assessment Committee, but it may have been a free floating mine.
The Kyokuyo Maru was fitted with two large funnels placed far aft and athwart- ships. She was also equipped with a large built-in stern chute. While obviously designed to handle whales, this chute may also have been used to launch mines or even midget submarines. Japanese whale-oil factory ships were built primarily for whaling expeditions, but their enormous tank capacities made them readily adaptable for petroleum transport duties. Several of them made pre-war calls in California oil ports.
At the end of the war and the beginning of the Empire’s reconstruction period, Japanese shipping companies were without floating equipment. The largest company, Nippon Yusen Kaisha, had once flown its houseflag on no less than 140 ocean-going vessels. In addition to its luxury liners on the transpacific run, it had some new and very commodious passenger ships operating from Yokohama and Hong Kong to London by way of Suez and the Mediterranean. Others plied in the China, Australia, and South American trades. This company, in which the Emperor had been a heavy personal stockholder, also had at least twenty “silk express” motorships running to Seattle, San Francisco, and Los Angeles, and to New York via Panama. When the surrender came in the late summer of 1945, just one ship of the former great N.Y.K. Line fleet remained in operating condition. She was the Hikawa Maru, which had served through the war as a hospital ship.
Osaka Shosen Kaisha was another famous company which lost its fleet. In addition to its transpacific high speed cargo carriers, this company had established and successfully operated a westbound globe-circling passenger and freight service. O.S.K. Line vessels in this service called at South African ports, rounded the Cape of Good Hope, touched at ports in South America and the Gulf of Mexico, then through the Panama Canal to California, and finally across the Pacific to their home port of Osaka. The company’s motorships usually made this entire world cruise on one bunker loading of diesel oil at Los Angeles.
The Kokusai, Kawasaki, Mitsubishi and Mitsui lines were among others which were stripped of their fleets by the war, together with all of the companies which had operated oil tankers.
Today Japan’s merchant fleet is being rebuilt on a long range, controlled program. It is quite unlikely that her famous luxury liners of former years will be replaced in the near future. By 1955 the Empire had 598 vessels of 3,242,000 gross tons in operation, and many more were building and on order. The new ships are for peacetime commerce, and are without the former firm commitment to an Imperial navy. It is a merchant fleet designed to serve the life lines of an industrial island-dwelling nation with 86,000,000 people, largely dependent on oceanic trade.