Takeshima Day: Persistently Demanding Resolution from South Korea Necessary

Editorial

16:35 JST, February 25, 2026

Japan-South Korea relations are on an upward trajectory, with leaders frequently visiting each other, confirming broad cooperation across various fields.

However, momentum for progress on the territorial issue has not improved. Precisely because South Korea is an important neighbor, Japan must persistently explain to South Korea that the Takeshima Islands are part of Japan’s inherent territory and strive for a resolution based on international law.

A memorial ceremony for Takeshima Day, organized by Shimane Prefecture among others, was held on Sunday in Matsue. A resolution was adopted calling on the central government to raise public awareness of the issue, strengthen the dissemination of information to the international community and support the prefecture’s research and investigations into the matter.

The ceremony, which marks the date the prefecture incorporated the islands in 1905, was held for the 21st time this year.

Territorial issues are fundamentally matters that the national government must take responsibility for resolving. The resolution’s content hits the nail on the head. The national government must further enhance its efforts.

There is no question that Takeshima is Japan’s territory both under international law and historically. South Korea raised no objection when Japan declared its incorporation of Takeshima. The San Francisco Peace Treaty following World War II also excluded Takeshima from the list of territories Japan was required to renounce.

However, just before the treaty took effect, South Korea unilaterally established the “Syngman Rhee Line” and began its illegal occupation of Takeshima. This situation is absolutely unacceptable.

Numerous documents have been found indicating that Japan had already established sovereignty over Takeshima in the early Edo period (1603-1868).

Documents were discovered two years ago confirming that several merchants from Yonago, Tottori Prefecture, were fishing on the islands with the permission of the Shogunate.

At the end of December, an illustrated map believed to date from the late 17th to early 18th centuries was discovered depicting Takeshima’s shape and other details. The prefecture announced last month that it had obtained the documents and the map.

The hard work by those who collected various materials as well as the efforts of Shimane Prefecture should be highly respected.

The government dispatched a parliamentary vice minister of the Cabinet Office to this year’s ceremony, as it has been doing in previous years. Prime Minister Sanae Takaichi had argued before assuming the post last year that a Cabinet minister should attend the ceremony. However, in the end, she followed established practice.

On the other hand, the Liberal Democratic Party sent its General Council Chairperson Haruko Arimura, marking the first participation of someone holding one of the party’s top three leadership positions. It appears that Takaichi, mindful of good Japan-South Korea relations, opted to send a party executive rather than a Cabinet minister.

The history surrounding Takeshima illustrates the reality that reclaiming territory is no easy task once illegal occupation is tolerated. The same applies to the northern territories.

China repeatedly intrudes into Japan’s territorial waters around the Senkaku Islands in Okinawa Prefecture. Japan must clearly demonstrate its resolve to protect its territory and sovereignty.

(From The Yomiuri Shimbun, Feb. 25, 2026)