Editor's note: Hou Yi is a researcher and the director of the Institute of Chinese Borderland Studies at the Chinese Academy of Social Sciences. The article reflects the author's opinions and not necessarily the views of CGTN.

China's resumption of the exercise of sovereignty over the Nanhai Zhudao was part of the institutional arrangements in reshaping the international order during and after World War II.

The South China Sea is a semi-enclosed sea and a vital maritime route connecting East Asia, Southeast Asia, and the Indian Ocean. In ancient times, the South China Sea region was one of peace and stability. However, the arrival of Western colonial powers led to turmoil as places such as Vietnam and the Philippines fell under colonial rule. Nanhai Zhudao – known in English as the South China Sea islands, historically part of Chinese territory, also became the object of Japanese and French colonialists. From the early 20th century through the 1930s, both Japan and France attempted to occupy these islands. The Chinese government back then strongly protested and adopted various measures to safeguard its sovereignty over Nanhai Zhudao.

With the outbreak of the full-scale Chinese People's War of Resistance Against Japanese Aggression, Japan seized and occupied the islands in the South China Sea. The Cairo Declaration, issued by China, the United States, and the United Kingdom in 1943, stated that all the territories Japan had stolen from China, such as Northeast China, Taiwan and the Penghu Islands, should be restored to China. Around Christmas that year, then U.S. President Franklin Roosevelt reflected on the Cairo Conference and discussions among leaders on particular long-term principles which they believed could assure peace in the Far East for generations to come.

The Cairo Declaration was reaffirmed in the Potsdam Proclamation issued in July 1945, which reiterated that "The terms of the Cairo Declaration shall be carried out." It also stated that Japan's sovereignty would be limited to its four main islands and such minor islands as the signatories might determine.

On August 15, 1945, the Japanese government surrendered to the Allies and announced its acceptance of the Potsdam Proclamation to China, the United Kingdom, the Soviet Union and the U.S. On September 2, Japan signed the instrument of surrender, which explicitly stated that it must faithfully fulfill the obligations laid down in the Potsdam Proclamation and unconditionally return the Chinese territories it had illegally seized.

In 1946, based on the Cairo Declaration, the Potsdam Proclamation, and the Japanese instrument of surrender, the government of the Republic of China recovered the exercise of sovereignty over the Dongsha, Xisha, and Nansha islands. In addition to establishing sovereignty markers and stationing troops across Nanhai Zhudao, the government reviewed the names of South China Sea islands. On December 1, 1947, then Chinese government published the "Table of Old and New Names of the South China Sea Islands" and released Nan Hai Zhu Dao Wei Zhi Tu (Location Map of the South China Sea Islands) in February 1948, on which the dotted line is marked.

These historical facts demonstrate that China's resumption of exercise of sovereignty over Nanhai Zhudao after World War II was part of the institutional arrangements by the Allies to dispose of Japanese-occupied but China-owned territories. This arrangement was made based on the fact that the South China Sea islands had always been a part of China and that China held legitimate rights and interests in the region. Thus, China's postwar recovery of exercise of sovereignty over Nanhai Zhudao, grounded in international agreements such as the Cairo Declaration, the Potsdam Proclamation, and the Japanese instrument of surrender, is legally valid and indisputable.

Jointly safeguarding the regional order of the South China Sea established after World War II

It is widely acknowledged that in the early 20th century, as imperialism emerged from capitalism, established and rising imperialist powers competed fiercely for colonies and spheres of influence. Their conflicts escalated into two world wars, inflicting untold suffering on people around the globe. At the same time, these wars also brought forth a new consciousness, dismantled the unjust international order set up in the aftermath of World War I, and led to the collapse of colonial systems. In their place emerged a new postwar international order centered on the United Nations.

The core principle of the new international order after World War II is multilateralism, built upon the United Nations as its foundation, with the UN Charter and other international treaties and norms as its legal basis. It calls for global cooperation in the service of all humanity, opposes hegemonism and promotes the international order and system to achieve greater fairness and justice.

On the South China Sea issue, China has always been a firm advocate for regional peace and stability, a strong promoter of its prosperity and development, and a consistent supporter of dialogue and negotiation to resolve disputes. The Chinese government has maintained a consistent stance, and it has made significant efforts to safeguard peace and development within the region.

In recent years, however, Western powers led by the U.S. have repeatedly interfered in South China Sea disputes, attempting to sow discord between China and its neighbors, and meddling in regional affairs. Such actions could undermine the postwar international order and foster a new form of hegemonism that only serves Western interests, which would trigger catastrophic consequences not only to the South China Sea region but also to the world as a whole.