Editor's note: Zhang Hua, a special commentator on current affairs for CGTN, is an assistant researcher at the Taiwan Institute of the Chinese Academy of Social Sciences. The article reflects the authors' opinions and not necessarily the views of CGTN.

Since late June, Lai Ching-te, leader of China's Taiwan region has been weaving a web of falsehoods and fallacies in Taiwan under the banner of "uniting Taiwan," using this as a platform to promote a repackaged version of the "two-state theory" that claims "the two sides of the Taiwan Straits are not subordinate to each other."

Behind this rhetoric lies not only an attempt to inflame anti-China sentiment and boost turnout in the so-called "grand recall" vote, but also a calculated effort to market his pro-independence agenda. In reality, these claims have no foundation in law and are fundamentally untenable.

From the perspective of international law, Taiwan's reunification with the Chinese mainland is a key outcome of the victory in World War II and an integral part of the postwar international order.

First, a series of documents with binding force under international law make it clear that China regained sovereignty over Taiwan de jure and de facto. On December 9, 1941, the Chinese government issued a declaration of war against Japan, and proclaimed that all treaties, conventions, agreements and contracts regarding relations between China and Japan had been abrogated, and that China would recover Taiwan and the Penghu Islands.

On December 1, 1943, the governments of China, the United States and the United Kingdom issued the Cairo Declaration, stating that it was the purpose of the three countries that all the territories Japan had stolen from China, such as Northeast China, Taiwan and the Penghu Islands, should be restored to China.

The Potsdam Proclamation was signed by China, the United States and the United Kingdom on July 26, 1945, and subsequently recognized by the Soviet Union. It reiterated "the terms of the Cairo Declaration shall be carried out." In September of the same year, Japan signed the instrument of surrender, in which it promised that it would faithfully fulfill the obligations laid down in the Potsdam Proclamation.

On October 25 of the same year, the Chinese government announced that it was resuming the exercise of sovereignty over Taiwan, and the ceremony to accept "Japan's surrender in Taiwan Province of the China war theater" was held in Taipei.

Furthermore, 183 countries around the world have established diplomatic relations with the People's Republic of China (PRC) on the basis of the one-China principle, recognizing that there is only one China in the world and that Taiwan is part of China. The one-China principle is a widely accepted consensus in the international community and a fundamental norm governing international relations.

Second, the legal grounds cited by Lai are entirely without validity. In his speeches, Lai references the Treaty of San Francisco and even distorts United Nations General Assembly (UNGA) Resolution 2758 in an attempt to legitimize his claim to "Taiwan independence."

The fact, however, is that the Treaty of San Francisco is both illegal and invalid. This so-called treaty was a unilateral post-World War II peace arrangement orchestrated by the United States and a number of allied countries, deliberately excluding both the PRC and the Soviet Union.

As established under international law and reaffirmed by the Vienna Convention on the Law of Treaties, "a treaty does not create either obligations or rights for a third State without its consent." Therefore, any arrangements to determine the status of Taiwan or any territorial or sovereign matters concerning China, which was not a party to the treaty, has no legal effect under international law.

From the outset, the Chinese government made its position clear: Since the PRC was not involved in the preparation, drafting or signing of the Treaty of San Francisco, it considers the treaty illegal and invalid, and does not recognize it. Other countries, including the Soviet Union, Poland, Czechoslovakia, the Democratic People's Republic of Korea, Mongolia and Vietnam, also refused to recognize its legitimacy.

On September 29, 1972, the Joint Communique of the Government of the People's Republic of China and the Government of Japan was issued. In it, the Chinese government reaffirmed that Taiwan is an inalienable part of the territory of the PRC. The Japanese government expressed full understanding and respect for this position and pledged to adhere to the provisions set out in Article 8 of the Potsdam Proclamation.

Lai's claim that "UN General Assembly Resolution 2758 does not mention Taiwan" is equally untenable. In October 1971, the 26th session of the UNGA adopted Resolution 2758, which undertook "to restore all its rights to the PRC and to recognize the representatives of its Government as the only legitimate representatives of China to the United Nations, and to expel forthwith the representatives of Chiang Kai-shek from the place which they unlawfully occupy at the United Nations and in all the organizations related to it."

It is true that the resolution does not explicitly mention the word "Taiwan." However, at that time, it was an internationally recognized fact that Taiwan was part of China. There was simply no need to refer to Taiwan separately in the resolution, just as there would be no need to mention any other province of China.

Moreover, alongside the adoption of Resolution 2758, the UNGA voted down proposals put forward by countries such as the United States and Japan that attempted to create a framework for "dual representation" or "one China, one Taiwan," as well as "Taiwan's self-determination." The rejection of these proposals demonstrates clearly that the UNGA did not recognize any notion of Taiwan as being independent. The specialized agencies of the UN later adopted further resolutions restoring to the PRC its lawful seat and expelling the representatives of the Taiwan authorities.

One of these is Resolution 25.1 adopted at the 25th World Health Assembly in May 1972. It was clearly stated in the official legal opinions of the Office of Legal Affairs of the UN Secretariat that "the UN considers Taiwan as a province of China with no separate status" and that "the authorities in Taipei are not considered to enjoy any form of government status." At the UN, the island is referred to as "Taiwan, Province of China." Taken together, Resolution 2758 settled once and for all the political, legal and procedural issues of China's representation in the UN, and it covered the whole country, including Taiwan.

Lai's attempt to distort this resolution by claiming it has "nothing to do with Taiwan" and asserting that "Taiwan does not belong to China" is a blatant misrepresentation of fact, a willful misreading of international law, and a direct challenge to the international order and the rules.

From the perspective of domestic law, Taiwan is an inalienable part of the sacred territory of the PRC.

On October 1, 1949, the PRC was founded, becoming the successor to the Republic of China (1912-1949), and the Central People's Government became the only legitimate government of the whole of China. The new government replaced the previous regime in a situation where China, as a subject under international law, did not change and China's sovereignty and inherent territory did not change. As a natural result, the government of the PRC should enjoy and exercise China's full sovereignty, which includes its sovereignty over Taiwan.

The Constitution of the PRC, adopted at the fifth session of the Fifth National People's Congress (NPC) in December 1982, stipulates: "Taiwan is part of the sacred territory of the People's Republic of China. It is the inviolable duty of all Chinese people, including our compatriots in Taiwan, to accomplish the great task of reunifying the motherland."

The Anti-Secession Law, adopted at the third session of the 10th NPC in March 2005, stipulates: "There is only one China in the world. Both the mainland and Taiwan belong to one China. China's sovereignty and territorial integrity brook no division. Safeguarding China's sovereignty and territorial integrity is the common obligation of all Chinese people, the Taiwan compatriots included … Taiwan is part of China. The state shall never allow the 'Taiwan independence' secessionist forces to make Taiwan secede from China under any name or by any means."

The National Security Law, adopted at the 15th meeting of the Standing Committee of the 12th NPC in July 2015, stipulates: "The sovereignty and territorial integrity of China brook no violation or separation. Safeguarding national sovereignty, unity and territorial integrity is the common duty of all Chinese citizens, including Hong Kong, Macao and Taiwan compatriots."

Even within Taiwan's own legal framework, relevant provisions acknowledge that Taiwan is part of China. For example, the opening clause of Taiwan's so-called "Additional Articles of the Constitution" begins with "to meet the requisites of the nation prior to national unification," which implies recognition of an unfinished process of reunification. This indicates that, even under Taiwan's own legal provisions, unification with the mainland remains an anticipated goal and Taiwan is part of China.

In summary, under both international law and China's domestic legal framework, there is no legal ambiguity: Taiwan is part of China. Any attempt to distort, misinterpret or selectively cite legal texts to fabricate a legal basis for "Taiwan independence" is doomed to fail and will ultimately prove futile.

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