Japan's Value in the Korean War Issues Surrounding the Dispatch of Minesweepers

Dr. Yoichi Hirama
(Radm Ret.) Professor of Naval History,
National Defense Academy of Japan


 In a speech at the Japanese National Defense Academy, former Korean Chief of the General Staff, General Pail Sun Yup once said,“during the Korean War when we were forced onto the Pusan beachhead, with the open seas behind us, there were enought supplies. The bases that supplied us were in Japan. And although because of the American Occupation it did not become an issue Japan was responsible for the minesweeping in Wonsan and Inchon. In that respect, one might say that in point of fact, Japan did participate in the Korean War."(1) It is true, in actuality, that Japan sent 44 minesweepers, 7 patrol boats and 2 guinea pig (trial ship that examine swept channels to ensure the safety of the ships behind it) to Korean waters. Because the new Guidelines for Japanese-United States Defense Cooperation in emergencies around Japan provide for "mine removal" and "exchange of information related to mines", I would like to examine the issues surrunding the little-known dispatch of the Special Minesweepering Flotilla, and thier activities, and their evaluation, in order to explore the management of the new Guidelines and their implications for both Japanese and Korean defense cooperation in the future.

1. Dispatch of the Special Minesweeping Flotilla

 Upheaval in Korea began when the North Korean troops crossed 38th parallel on June 15, 1950; Korean and American, British and other forces under the United Nations (UN) banner, lacking heavy armaments and tanks, were forced into retreat after retreat. The fate of the UN forces, squeezed onto the Pusan beachhead, flickered like a light in the wind, and the world anticipated the advent of "the Asian Dunkuerk." What saved the world from such a crisis was the United States Army stationed in Japan, and the rapidly assembled United States Air Force in the Far East region, which used bases in Japan (Ref.Appendix 1).

 It was the September 15 surprise landing attack at Inchon that turned the United Nation's defensive tactics to those of a desperate military situation. The UN troops that landed at Inchon had taken Seoul in one week, and Douglas H. MacArthur, the powerful UN General Commander, had planned a landing at Wonsan on the eastern coast for October 15. The North Korean forces, weak in naval power, had laid approximately 3000 mines in ports in every region with the Soviet Union's assistance. When a mine was discovered off the Western shore of the Korean peninsula on September 7, Rear Admiral Allan E.Smith's message beginning “The U.S.Navy lost control of the sea......." was transmitted to the Pentagon. Commander in Chief of the Pacific Fleet then dispatched a mine alert message on September 11. In order to sustain naval gunpower to support the army attacking on shore, to secure supply ports for UN forces, and also to conduct the on-land strategy to divide the North Korean forces into east and weat landing at Wonsan, a number of minesweepers were required. However, the South Korean navy's minesweepers were not properly equipped, their training level was low on that times, and according to the U.S. Pacific Fleet Interim Evaluation Reports, “Republic of Korean YMS - Although ROK YMS accompanied both the Wonsan and Chinnanpo Minesweeping Groups, they were not equipped with minesweeping gear and were not adequately trained to be entrusted to "danning(setting buoy where mines are located)" rsponsibilities. In both area they were used destruction vessels, pilot ships and couriers. These ships performed cheerfully and willingly and their officers, in genenral, were alert and intelligent."(2)

 In addition, 99 percent of all World War minesweepers were reserves condition, and between 1945 and 1950, due to demobilization, budgetary cuts and a lack of naval interest and emphasis on mine warfare, those trained crews had vanished and their ships had been reactivated, sold, or scrappted. The U.S.navy's minesweepers had been withdrawn, and of those remaining in the East, four were steel (of which three were in reserve) and six were wooden supply ships. Those officers and sailors with experience in mine warfare and minesweeping skills had been deactivated and the capacity of every ship had been cut in half.(3) Meanwhile, Japan had 84 minesweepers and 4 guinea pigs that composed what the U.S Navy called "a superb force skilled in minesweeping operations. In spite of their small size, low horsepower and inadequate degaussing,the Japanese sweepers have in the last five years shown themselves worth while in sweeping World War mined areas. These ships were well trained and ready to perform minesweeping by experienced personnel."(4)

 On October 2, Maritime Safety Agency Director General Takao Okubo was summoned by Rear Admiral Arleigh A. Burke, Special Staff for to Vice Admiral Turner Joy for the Commander of the U.S.Naval Force in the Far East, and was asked by Admiral Burke to "assemble every one of your mine-sweepers in the Tushima Straits area and assist in the Wonsan mine clearance, and help the check sweep of the Inchon main approach channel and harbor."(5) Because Director Okubo believed "the request was important, and not a question that one person alone should decide," Director Okubo went immediately to see then-Prime Minister Yosida Shigeru, presented the sequence of events, and solicited the Prime Minister's direction.(6) Faced with this difficult choice, Prime Minister Yosida called for the dispatch of the minesweepers:“the policy of the Japanese government is to cooperate with the UN forces.(7) Following the official order from Rear Admiral Joy was dispatched.(8)

CNFE/S81 5451
4 Oct.1950
From:Commander Naval Force,Far East.
To:Ministry of Transportation, Japanese Government.
Subject:Japanese Minesweepers, use of.

1. The Japanese Government is hereby directed to assemble twenty Japanese Minesweepers, one guinea pig and four other Japanese Maritime Safety vessel in Moji as soon as practicable. Those vessels will be designated in future directives.

2. The above twenty Japanese Minesweepers will not include MS No.12,13 and 17 presently sweeping in Tokyo Bay, or MS No.22, 25 and 26 currently sweeping in Sasebo.

 The Maritime Safety Agency immediately announced its order to "assemble at Moji the minesweepers and patrol boats indicated in order to implement the minesweeping of the Korean channel as per the United Stated Navy's command,"(9) and Director of the Mine Clearance Division of the Maritime Safety Agency, Kyuz Tamura(future Maritime Self Defense Force, Vice Admiral) was named Commander of the dispatched Special Minesweepering Flotilla.

2 Conditions of the Minesweeping Operations on the Korean Peninsula

(1)The Second Minesweeping Division's Separation from the Lines of War.

 Nose Sh go (future Maritime Self Defense Force, Rear Admiral), then Chief of the 5th Minesweeping District in Kobe, who had been appointed Commander of the Second Minesweeping Division, approached the process of clearing the floating mines(a floating mine is a mine with its mooring wire cut), positively accepted the request without hesitation, saying "I am at your command." However, upon arrival in Moji, his division was informed that "Japanese Minesweepers will be designated Task Unit 95.66; they will be under the direction of the Commander of the Seventh Fleet, all vessels assigned to this duty in Korean Waters will fly only a modified International "Echo" flag, and marks, including those indicating vessel names and pennant numbers will be removed." They were given an explanation of the Korean region and about 12 items of safety instruction about mines. Distrust, anxiety, and fears that the meine-sweeping of the Korean channel was not simply the disposal of floating mines but an entry into the Korean War spread among the skippers who heard this explanation. Their fears were summerized in a question raised by commander Tamura;“Is not entering under the direction of the current U.S.Naval commander in Korean tantamount to entering the Korean War? And is that not a violation of our constitution?" It is said, however, that Commander Tamura was unable to get a precise answer to these questions.(10)

 At that time when the Japanese constitution had just been officially announced and the world was brimming with peaceful sentiment, the non-military officials of the Ministry of Transportation received their orders to go to war. Upon hearing the dispatch order, families pulled their husbands from the neatly moored ships, and persuaded them, with tears running down their cheeks, that even though the war had ended they were not going abroad to fight another war this time. The feeling of the Minesweeping Flotilla members, expressed in a meeting before the dispatch, was that "there is no reason to endanger our lives by putting ourselves up to the dangerous task of fighting a war for another country, when according to Japan's new constitution we abolished war. Furthermore, we are not soldiers anymore, but citizens who have labored voluntarily to clear mines within Japanese territory in the name of the mission to rebuild Japan. We cannot consent to go to war to clear the seas of a foreign country."(11)

 The Second Minesweeping Division (four minesweepers, three patrol boats) left Moji port at four in the morning on October 8 with Commander Tamura's flag-ship Yuchidori in the lead, and arrived at Wonsan early on the morning of the tenth. The minesweeping operation began at the approach for Wonsan harbor the following day, and on the 12th, minesweeping began in the main approach channel to Wonsan, a channel of approximately 15 nautical miles and 2000 meters in length with U.S minesweepers Pirate and Pledge. However,as soon as they had entered the port, the Pirate hit mines and sank before their eyes, leaving 12 dead and 92 wounded. As a result, minesweeping was temporarily stopped, but as the scheduled date for the start of the landing operation was approaching, mine-sweeping recommenced outside the bay on the 14th, and inside the bay on the 17th. Minesweeper No.14 encountered a mine inside the bay and sunk within minutes, leaving one sailor dead in the line of duty, two critically wounded, five seriously wounded, and 11 sailors with minor injuries.(12) The skippers of the ships that had stopped minesweeping operations gathered on the flagship Yuchidori, and the skippers agreed:“This is nothing like what they promised. We were forced into silence." They advocated halting mine sweeping operations, agreeing that:“We do not want to get any more involuved in this war than we already are. We must stop the minesweeping and return to Japan." Director Tamura and other staff persuaded conducting the Japanese preparatory method, borrowing small boats from U.S. Navy for the initial minesweeping operations. This proposal was approved by skippers and the Commander of the Third Minsweeping Squadron, Capt. Richard T. Spottford. But the Japanese request was subsequently overruled by the Commander of Advance Fleet, Rear Admiral Allen E. Smith, who said:“From now on, there is not enough time to conduct preparatory minesweeping operations. You will be conducting quick anti-ship sweeping operations, as per the original plan." Japan presented a revised plan, but Admiral Smith's firm response was:“Leave the anchorage tomorrow moring at 0700 hours and continue minesweeping operations. Otherwise, return to Japan. If you do not leave within 15 minutes, I will fire - the Japanese misheard “fire". Mistaking “hire" for “fire", the Second Mine-sweeping Division pulled minesweeper No.17, then under repair due to engine failure, turned toward Japan, and left Wonsan. The Japanese government immediately dispatched the Third Minesweeping Division(five minesweepers and three patrol boats), and the First Minesweeping Division(six minesweepers and one patrol boat). Meanwhile, three skippers and Director Nose, upon returning home from Wonsan were forced to retire under the pressure of the U.S.Navy.(13)

(2)The Minesweeping Operation in other areas

 At the same time, the First Minesweeping Division(four minesweepers and one patrol boat) that had been heading for Inchon, gathered at Moji port on October 4. Leaving the harbor for Inchon on October 7. Those minesweepers to the Korean waters had not had enough time to conduct repairs on the ships and to make administrative arrangements. Both the First and other minesweeping divisons later dispatched were sent to areas occupied by the U.N Forces; except for the sinking of one minesweeper, there were no significant problems. But for those minesweepers thrown from peaceful existence into war in a single instant, in wooden boats built hastily at wartime, their hulls worn out from continual minesweeping around Japan after the war, in areas affected by the severe cold the Sea of Japan and the Yellow Sea, with the rough winter winds, the problems with supplies, the lack of water, and the necessity of cooking rice gruel with cider - the hardships the men encountered were beyond description.

 "At night, a small boat filled with elderly people approached our boat where we were anchored, and the people on board asked that if we had rice meal to feed the infants. They had neither lamps nor matches. Nothing. Nothing at all. The sailors, watching an old woman crawl into the crashing sea to find shells and seaweed to help her family stem their hunger, could not sit idly by. They gave lamp oil, rice, condensed milk, and matches." "By day, war, by nignt refuge rescue. Could I ever have imagined such things before we left port?"

 Recalls one officer who participated in minesweeping operations in Korean at that time.(14) Yamanoue Kamez (future Rear Admiral), Commander of the First Mine- sweeping Division, offered his perspective:

 "It is difficult to seaech for advanced mines using such old and weak techniques and minesweeping equipments, "to be able to clear mines with the most bitter cold of the winter season in nearby North Korea,“that we could not complete our duty was more clear than light itself." “To attempt duties beyond our ability is extremely dangerous." His opinion, however, passed unrecognized.(15)

3 The Minesweeping Flotilla's Successes

 The Special Minesweeping Flotilla was divided into minesweeping units and guinea ship unit, and as Appendix 2 shows, in the two months from mid-October to early December 1950, the minesweeping units were engaged in minesweeping in Wansan, Inchon, Haiju, and Chinnapo, and from November 18 to 30, the guinea pigs the Taisho-Maru and Souei-Maru cleared Inchon, Mokpo, Wonsan, Masan, Pusan, Chinhae ports and main entrance channels. The seven division, 44 minesweepers, 7 patrol boats and two guinea pig ships that comprised the Special Minesweeping Forces cleared an channel of 327 km, and anchorage of 607 square km2, and disposed of 27 mines. One minesweeper exploded, sank, and was left at sea; one sailor died, and 18 were injured at least critically.(16) For approximately three years from July 16, 1950 to September 16, 1953, 43 Minesweepers were also committed to conduct check sweeping at the entrance of the U.S.Naval Bases Sasebo and Yokosuka.(17) Additionally, because a number of floating mines were sighted in the Sea of Japan, and also a number of floating mines were found drifting ashore before and after the outbreak of the Korean War, the Maritime Safety Agency formed floating mine search and disposal units in the Sea of Japan which were composed of minesweepers and mine-observation unit on land along the coast of the Sea of Japan, and is indicated below, they disposed of 189 mines, at shore or at sea.(18)

Floating Mines in the sea and on beaches
conditions/years 1950 1951 1952 total
sighted mine report 140 267 112 519
disposed at sea 44 28 22 94
disposed on beach 35 51 9 95
explored on beach 4 17 9 40

 3000 mines had been laid in the area along the Korean coast, and compared to the 312 mines disposed of by the U.N.forces, the Japanese Minesweeping Flotilla's contribution of only 33 mines was insignificant. However, when war broke out, the U.S.Navy had only one operational minesweeper and six support miensweepers without the appropriate equipment for minesweeping in the Far East, and although they quickly sent mine sweepers from Philippines, Guam, and the American west coast, by November 30, there were only 19 minesweepers altogether. In contrast, Japan contributed 32 ships to the minesweeping operations.(19) In the “First Interim Evaluation Report on the Pacific Fleet in the Korean War," the Pacific Fleet Command recorded that “Japan's minesweepers, having obtained the permission of the Allied Forces to participate, contributed greatly to the tactical success," and “the recommissioning of the minesweepers after September, coupled with the use of Japanese minesweepers, allowed us to meet the North Korean mine-layers from our disadvantage, and by November we had improved our mine-sweeping capability to an acceptable level."(20) Beyond saving the Allied countries from their dire need for minesweeping manpower at the beginning of the war, Japan's minesweeping units made a big contribution indeed. This is clear in Rear Admiral Joy's presentation of war rewards:

 "The rapidity with which your forces responded to the request to do minesweeping in Korea, the quality of their work, and their spirit of cooperativeness have given me great pleasure. It is recognized that they had many difficulties with weather, language and supplies, but by perseverance, and working under the efficient supervision of Director Tamura, Chief of the Mine Sweeping Division of Maritime Safety Agency, they overcame them all. With pleasure, I ask you to transmit to all hands concerned,Well done".(21) That these rewards were not simply for foreign services is confirmed in the Pacific Fleet Command's “Interim Evaluation of the Korean War":

 "The Japanese minesweepers assigned duties in Korean waters performed in their customary reliable fashion. Three ports on the Korean west coast were independently swept by the Japanese under British control, while other ships swept at Wonsan and Chinnampo. At Wonsan one JMS was mined and sunk while sweeping shallow moored mines. The following day, due primarily to language difficulties and consequent misunderstanding, three of the remaining JMS left the area and returned to Japan. The personnel of these three ships were dismissed from minesweeping service. In all other cases, although the language problem persisted, the Japanese swept for both moored and magnetic mines under adverse conditions of weather and logistic support."(22)

 "Sweep gear handled and functioned well. The Japanese bar magnetic drag sweep has a narrow path and required good boat navigation. View of this simplicity its actual effectiveness should be compared to U.S. B-8 magnetic wire sweep."(23)

 "The Japanese sweepers employed at Wonsan, Chinnampo, Haeju and Junsan sweept for both moored and magnetic mines. The performance of personnel was good.Considering the low horsepower of these ships operations were satis-factory.... All sweeping was considered done in a satisfactory manner."(24)

In conclusion

 Japanese minesweepers activities during the Korean War were as explained above. Not only did Japan provide mine sweeping to clear harbors and channels for port approaches to support, but Japanese also provided supports for both land operations and post-battle operations by conducting the daily checking sweeps, at the U.S. Naval bases in Japan, and also by disposing of floating mines in the Sea of Japan. Japan also allowed the United Nation's Air Forces, which had lost its air bases in the Korean Peninsula use of Japanese airport for direct attacks on the southern part of the Northern Korean troops, as is shown in Appendix 1. Additionally, the value of the rear-area support from Japanese bases in the Korean War is clear from the yearly contracts for staple materials and services as indicated in the table below.(25)

Yearly Contracts for Staple
order/year 1950 1951 1952 1953 1954
1 truck car-parts arms arms arms(☆)
2 cotton goods coal coal coal coal
3 blanket cotton goods hemp bag food food
4 construction can barbed-wire furniture furniture
5 hemp bag hemp bag cement a dry cement batter
                           (☆)mainly ammunitions

Contracts for Staple of materials and services(unit:1000$)
items materials services price
1 arms 148.489 constructions of structure 107.641
2 coal 104.384 repair of car 83.036
3 hemp bag 33.700 storage・transportation 75.923
4 car-parts 31.105 elephone-communications 71.210
5 cotton goods 29.567 repair of machines 48.217

 Although two mineseepwers sank and casualties and injuries occurred during minesweeping operations in the war zone, hardly any members of the minesweepers left the operations. This may be an order of an Occupation Forces, as that time Japan was under occupation by Allies; but I also believe it was because the force members had agreed to work for the United Nations.(26) Additionally, the advantageous Allied position on the Korean peninsula, the peace of mind born of the UN troops control of air and sea supermacy, and the intimacy and feeling of bringing "the backbone of the Imperial Navy" that came from sleeping and eating together as members of the former Imperial Navy family contributed to the members solidarity.(27)

 However, nothing was more important than the leadership of Prime Minister Yosida, who dispatched the minesweeprs. When the Second Minesweeping Division refused to perform its operations and returned from Wonsan, Prime Minister Yosida gave them this message: "We must fully cooperate with the UN Forces, in order to give our country full advantage in the independent of Japan for Peace Conference. I know that you met with great adversity conducting minesweeping operations with small, worn-out ships in the harsh weather in Korea, but I ask you to answer to the U.S.Navy's request and to bring all of your strength to bear on the minesweeping operations. Beassured that we will do what we can to lend a hand in the treatment by the government."(28) This prime ministerial leadership made minesweeping operations possible in the Korean contingency.

 Minesweeping operations required a tremendous expenditure of logistic support, it involved close coordination with other fleet activities, extensive training, and a variety of equipment: tenders, mother-ships, small boats, mine disposal units and underwater demolition teams. The Korean War proved that mine warfare demands many minesweepers over a long period of time and that minesweeping in battle areas is not just an investiment of a few minesweepers for disposal of floating mines but of many vessels over a long period of time. If we compare the conditions during the Korean War with those today, the biggest difference is that Korea now has the minesweeping strength of 14 minesweepers. Yet, of that minesweepeing strength, eight are old-model craft acquired from America and built in the 1950s, and only six are the newer-model mine-hunter type. Even the U.S. Navy only has three mine-hunters in the Far East region. By contrast, the Maritime Self Defense Force has two minesweeping mother ships, and 34 newer-model mine-hunters - which is not very different from the combined minesweeping strength of Japan, Korea, and United States Navy during the Korean War.(29) But the biggest change is the limitation of area by Japan's new constitution and that even in the new Guidelines for Japan-United States Defense Cooperation, the area in which Japan can clear mines is limited to Japanese territory and the high seas. Although the prime minister's order enabled the dispatch of minesweepers during the Korean War, today the popular sentiment in both Korea and Japan has changed dramatically. According to a Yomiuri Shinbun opinion poll, 83 percent of people in South Korea say they "cannot trust Japan", while in Japan, 49 percent of the people surveyed say they "cannot trust Korea". In addition, in response to the question “how do you view Japan ?" 70 percent of Koreans said as a rival, and 19.7 percent said as an "enemy".(30)

 While the Guidelines for Japan-United States Defense Cooperation were established in response to to the American demand for a certain degree of cooperation, with its attendant defense expenditures and other sacrifices, in the case of an event on the Korean peninsula, what Japanese politician could press for the sacrifice of his own people in the midst of such mutual malevolence for a country that expresses such anti-Japan, Japan-hating criticism?

 The people of Japan and South Korea should understand that if American were to ask Japan for even more support in a crisis in Korea, and the anti-Japanese sentiment in South Korea were to remain unchanged, damages and tragedies would fall more on South Korea than Japan, and the result would affect not only on Korea and Japan, but all Asian countries. The destiny of Asia must not be decided by narrow-minded Japanese and Korean nationalism. If both countries could make a steady and continual effort to refrain from making statements that incite such emotional confrontation, the Guidelines might function in a Korean contingency. Finally as a sailor, I would like to conclude with the suggestion that to atempt to improve the effectiveness of the Japan-United States Security Alliance without an understanding of military affairs, including Japan's achievements in rear-area support and mine sweeping operation during the Korean War and the nature of mine-warfare, the story of our national security is but a tower built on sand.

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