“The Name of the Sea of Japan and Flaws with theKorean Arguments” Q&A*Masao Shimojo(Professor emeritus at Takushoku University and a visiting professor at Tokai Universityand the University of Shimane)
Q1 In 1992, the delegations of South Korea and North Korea raised their objection tothe name “Sea of Japan” at the United Nations. Does this indicate that South Korea andNorth Korea are working together regarding this issue to jointly make such claims?
When it comes to historical issues, South Korea and North Korea tend to cooperate with eachother. Both countries have taken similar positions on history issues, partly because it is a good
diplomatic means of mounting an offensive against Japan. This continues to be the case today.
Q2 Based on the Aguk ch’ongdo ( 我 国 総 図 , complete map of Korea), it would seem
natural for South Korea to ask that the sea now internationally known as the Yellow
Sea be called “West Sea” and the East China Sea be called “South Sea.” Why does
South Korea make the claim that it does only with regard to the Sea of Japan? In thisconnection, is there any discourse in South Korean academic circles that says that such aclaim should be made? Has this discourse reached the Korean government?
Another reason for the South Korean side to have taken up the East Sea issue is the existenceof Takeshima in the Sea of Japan. South Korea has illegally occupied Takeshima since 1954, andTakeshima is located in the Sea of Japan. Moreover, they say that the name of Takeshima is not
Takeshima, but Dokdo. If Dokdo is in the waters of the Sea of Japan, it is inconvenient because itlooks like Japanese territory. So South Korea needs to have the name changed to “East Sea,” theKorean name, and assert sovereignty over Dokdo. This means that the naming of the Sea of Japanand the Takeshima issue are connected. From the South Korean side, therefore, the East Sea
becomes an issue because of the Takeshima issue. Since there is no territorial dispute over the* This article is a summary of the Q&A section of the JIIA webinar “The Name of the Sea of Japan and Flaws withthe Korean Arguments,” presented by Professor Emeritus Masao Shimojo of Takushoku University on September 13,2022. In the webinar, Professor Shimojo explained in a comprehensible manner his views, based on his many years ofresearch, on the flaws in the South Korean arguments regarding the name of the Sea of Japan on the grounds of oldmaps and documents. The views expressed in this publication are those of the author and do not necessarily reflect
the policy or position of The Japan Institute of International Affairs or any other organization with which the author isaffiliated.

A full video of the webinar is available here:
JIIA webinar “The Name of the Sea of Japan and Flaws with the Korean Arguments”
https://www.jiia-jic.jp/en/events/2022/09/the-name-of-the-sea-of-japan-and-flaws-with-the-korean-arguments.html
Please also refer to the following article related to the subject of this webinar:“The Name ‘Sea of Japan’ Is the Only Internationally Established Name (The Debate Concerning the Naming of the Seaof Japan - Analysis of the South Korean Government’s Arguments Based on Historical Materials and Maps-).”https://www.jiia-jic.jp/en/resourcelibrary/pdf/EN-The_naming_dispute_of_the_Sea_of_Japan.pdf

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The Japan Institute of International Affairs / Resource Library“The Name of the Sea of Japan and Flaws with the Korean Arguments” Q&A

South and West Seas, South Korea shows an inordinate interest only in the East Sea. The Takeshima
issue is behind the reason why the name of the Sea of Japan is in question.
Q3 Have there been any other disputes between countries over names used by theInternational Hydrographic Organization (IHO) like the one over the name of the Sea ofJapan? If so, how were they debated, and were they ultimately resolved?
I am unfamiliar with the specifics, as I have not attended these meetings of the International
Hydrographic Organization (IHO) or the United Nations Conference on the Standardization of
Geographical Names, but South Korea appears to be the only country that is making an issue ofhydrographic names. In that respect, again, this issue relates to the Takeshima issue. Also, South
Korea’s perception of history is a little different from that of other countries. It can be said that thesecharacteristics of South Korea are reflected in those issues.
Q4 Considering the point you made that the South Korean side cherry-picks notations
scattered in old documents that have nothing to do with the Sea of Japan—such as that
“East Sea” and “Blue Sea” ( 滄 海 ) denote the coastal waters of the Korean Peninsula
and that the sea to the west of the Korean Peninsula was called “East Sea,” as in the sea
to the east of China—to make their case, it seems that the South Korean side lacks valid
evidence for their claims. What do South Korean researchers think about this? Could youtell us what kind of discussions you have had with South Korean researchers?
I myself am in a dispute with South Korea over the Takeshima issue, and South Koreans do notlisten to the opinions of those who make claims that are inconvenient for them. They ignore such
opinions. So even if it became evident that the East Sea was not the Sea of Japan, I believe thatSouth Korea will continue to want to use the name “East Sea” for the Sea of Japan and that suchmoves will continue in the future. In fact, although it was recently decided at the IHO that the name“Sea of Japan” should be used exclusively, the South Korean side remains intent on promoting thesimultaneous use of the name “East Sea” and continues to conduct propaganda and information
warfare to that end. As long as there is no specialized organization in Japan to debate these historicalissues with the South Korean side, South Korea will continue to make one-sided statements. We thus
need to lay down a research structure such that we can refute each of the claims made by the South
Korean side. In South Korea, if something is inconvenient for them, they will turn a blind eye. On theother hand, if they sense that the other side is weaker, that is, if the Japanese side does not clearly
refute the South Korean claims, the South Korean side will keep repeating the same arguments; thatis their tendency. Hence, when considering historical issues with South Korea, I think it is necessary
for Japan to constantly disseminate information. But to transmit that information, research of thatnature needs to be conducted on a daily basis. Unfortunately, as with the Takeshima issue, there arevery few researchers on the Japanese side who are engaged in sustained research on such issues.
There are also no specialized research institutions. As such, Japanese has no sustainable research
institute—“sustainable” being a buzzword these days—no institute for sustainable research to put
an end to the claims of South Korean side. I therefore think it is absolutely essential that we keep
pointing out the errors in the South Korean claims by continuing our research.
Q5 If we are debating whether the name “Sea of Japan” is a remnant of the colonial
period, is it important to ask what the global perceptions were before and after thecolonial period and how the maps changed? If so, are there any authoritative maps of the2The Japan Institute of International Affairs / Resource Library“The Name of the Sea of Japan and Flaws with the Korean Arguments” Q&A

world that refer to the “East Sea” in precolonial times?
There is the Kanei suiroshi (Kanei Hydrography), published I think in 1887, which was modeled
after British hydrographic journals. As such, the name “Sea of Japan” had already been establishedby the end of the nineteenth centur y. Meanwhile, South Korea came to have the historical
understanding that the Sea of Japan is the East Sea only after World War II. And based on thishistorical understanding, it replaces all past references to the “Sea of Japan” with “East Sea.” The
South Korean way of research is not to gather various documents and make judgments inductively;
rather, it is deductive.
In short, first there is the claim that the Sea of Japan is the East Sea, and when they findreferences to “East Sea” in Chinese or Korean literature, they have a strong tendency to interpretthese sources in a way that suits their needs. Unless we have the research ability to debunk this, wewill end up repeating the same historical problems with South Korea or with North Korea. In thatregard, the issue of the name of the Sea of Japan is not complicated, since it does not involve humanrights issues, as in the cases of wartime “comfort women” or conscription of Korean laborers. It is
possible to debunk the claims of South and North Korea by accumulating objective facts. As such,I believe that Japan should use the name of the Sea of Japan as a diplomatic bargaining chip. To doso, Japan must have a scheme in which it can clarify or understand South Korean and North Korean
attitudes toward historical issues and then refute them.
Q6 You have made it clear that the South Korean claims are a fabricated history to suit
their own purposes. Is this campaign by the Korean government for the simultaneoususe of the name “East Sea” alongside “Sea of Japan” still ongoing? How should Japan
respond to such moves, including by disseminating information?
Regarding the issue of the name of the Sea of Japan—which South Korea sees as the “EastSea issue”— about nine days before the passage of the “Takeshima Day” ordinance that Shimane
Prefecture set out to establish, South Korea created a bill for conducting sustained research related
to the Takeshima issue. It was in September 2006, I think, that a state-run research institute called
the Northeast Asian Histor y Foundation was established. The institute engages in research on
all fronts, including the Sea of Japan issue, the Takeshima issue, the comfort women issue, andthe wartime labor issue. Ever y president of the Northeast Asian Histor y Foundation has beena historian. A historian sits at the top, and this position is equivalent to that of a state minister.
There is a staff of about 100 under the president, about 60 of whom are history experts, and 40 aresupporting staff. They engage in sustained research under this framework and reflect the results inforeign policy. The Northeast Asian History Foundation functions as a policy advisory organizationfor South Korea. Unfortunately, there are no such think tanks in Japan. As such, South Korea will
likely continue to fabricate history in various ways, and it will bring various historical issues to thefore and use them as diplomatic trump cards. What this means is that Japan and South Korea havecompletely different perceptions and stances on historical issues. Whether in the case of Takeshima,
the Senkaku Islands, or the Northern Territories, or in the case of the abduction issue with NorthKorea, Japan is always on the defensive rather than on the offensive. To proactively resolve theseissues, then, Japan will need to conduct research and establish a scheme such that it will be able towage information warfare or cognitive warfare overseas. This is the same as waging war, albeit awar that does not involve military force, and what is important is the logistics route for continuingsuch disputes. We need to develop institutions for research and generations of researchers who can3

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conduct such research. There is no point in waging an information war without creating missiles ofinformation.
In that regard, Japan lacks the tactics and strategies to constantly create and disseminate
information. Given this current situation, the historical warfare and historical perception issue
with South Korea will continue. As for how to break the deadlock, Japan’s political and diplomatic
capacity will be key. That is where Japan is lacking. If we can improve in this area, it will be possible
for Japan to defeat the false historical perceptions of the South Korean side that I talked about today.
Without doing that, I believe Japan–South Korea relations will always remain in the worst state. Andthe countries that would be most pleased with that are North Korea, Russia, and China. Whether
with regard to the historical issues between Japan and South Korea or between Japan and China,
or with regard to the name of the Sea of Japan, which I just discussed, it is time for Japan to present
recipes for their resolution. Moreover, I believe that now is the last chance to do so. I would likeyou, the listeners, to be aware of this. The historical documents that the South Korean side or theChinese side use as arguments for Takeshima, the Senkaku Islands, or the name of the Sea of Japanare virtually all being perverted. They are not interpreting the sources correctly. The problem is that
South Korea and China do not realize that they are not correctly reading the documents. Even if they
do, they are unable to retract their flawed claims. This is because there has been no strong rebuttal
from the Japanese side and no sustained offensive.
In relation to the Sea of Japan issue, the South Korean side has been engaged in propaganda
activities in the United States and other countries by working with such people as KoreanAmericans. In Virginia, Korean Americans have played a central role by cooperating with lawmakers
in election campaigns and, in that process, pushing for the simultaneous use of the name “EastSea” with “Sea of Japan.” This eventually led to the passage of a bill in Virginia for the simultaneoususe of the names “East Sea” and “Sea of Japan,” and this move would then spread to about sevenother states. At the time, the aforementioned Northeast Asian History Foundation actively backedup the bills. Historically, the Society for East Sea, a group under the South Korean government
mainly comprising South Korean geographers, has spearheaded the drive for the simultaneoususe of the name “East Sea” since the 1990s. When research groups like the Northeast AsianHistory Foundation and the East Sea Research Association, which have close ties with the Korean
government, participate in the movement to promote the use of “East Sea” alongside “Sea of Japan,”this arouses ethnic sentiment among Korean Americans, which in turn leads them to serve their
homeland. This inevitably becomes linked with the South Koreans back home and leads to antiJapanese behavior. If Japan fails to respond appropriately to this trend, that failure will be taken
advantage of, and Japan–South Korea relations will become even more difficult. As you can see
from what I have shared with you today, there is virtually no basis for the problems of historicalperception claimed by the South Korean side. However, I think there is also a big problem with thestandard, if you will, of the Japanese side, which failed to recognize this. In historical issues, we needto do more than just criticize South Korea and China; we must also correct the course of Japan’scurrent situation so that we can engage in historical information warfare. Now is the final chance todo so.

This paper was translated by JIIA from Japanese into English with the author’s consent in 2022.
JIIA takes full responsibility for the translation.
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