I.  The Post-war Treaties

In 1951, the Allies and Japan signed an international treaty in San Francisco. The treaty came into force on April 28, 1952. Article 2(b) of the treaty provides that:

Japan renounces all right, title and claim to Formosa and the Pescadores.

Neither the People's Republic of China (PRC) nor the Republic of China (ROC) were invited to the peace conference to sign this San Francisco Treaty.

Indeed, from a legal point of view, it can be argued that neither of these governments had "legal standing" to sign the treaty. Much support for this view can be gleaned from a thorough examination of the historical details. In the case of the PRC, it was founded on Oct. 1, 1949, and therefore had no military forces which participated in the WWII fighting. Consequently, there was no legal rationale for it to sign the peace treaty. As for the ROC, it already moved its central government to Taiwan by mid December 1949, an area which legally speaking was not Chinese territory, because no treaty had recognized it as such. Before the coming into force of the peace treaty, Taiwan was still the sovereign territory of Japan. In fact, by leaving its own national territory, ROC had degraded itself to the status of a government in exile, with the result that its ability to serve as the true representative of the Chinese nation was in serious question.

A further a bilateral treaty was signed between the Republic of China government (in exile in Taiwan) and Japan on the same date of April 28, 1952, and came into force on August 5 of that year. The Treaty of Peace between Japan and the Republic of China (commonly called the "Treaty of Taipei"), is a subsidiary treaty under Article 26 of the San Francisco Treaty. In Article 2, it recognizes the pre-existing renunciation provision. The wording is as follows:

It is recognised that under Article 2 of the Treaty of Peace which Japan signed at the city of San Francisco on 8 September 1951 (hereinafter referred to as the San Francisco Treaty, Japan has renounced all right, title, and claim to Taiwan (Formosa) and Penghu (the Pescadores) as well as the Spratley Islands and the Paracel Islands.

The Treaty of Taipei was later abrogated by the Government of Japan upon its establishment of diplomatic relations with the People's Republic of China on September 29, 1972.

II.  China's Claim to Taiwan

Chinese scholars typically ignore the provisions of the San Francisco Treaty entirely. As for the Treaty of Taipei, they like to claim that as a treaty between two parties, when one "renounced" the other must have "received." Accordingly, they interpret Article 2 to say that Taiwan belongs to China.

Since such arguments have failed to convince the international community, an alternative, and more widely promoted idea is to say that Taiwan was "returned" to China on either September 2, 1945 (with the signing of the Instrument of Surrender) or on October 25, 1945 (when KMT troops accepted Japan's surrender in Taipei). Based on this line of reasoning, Taiwan was already "a part of China" when the Communist Party won the civil war in 1949, and established the PRC in Beijing on Oct. 1st. An examination of the "successor state theory" then shows that all agreements signed by the previous government (including those agreements regarding boundaries) are binding on the successor government. Therefore, the conclusion can be reached that Taiwan belongs to China.

III.  Examination of International Law Regarding Transfer of Territory and Related Issues

However, when these claims are illuminated under the light of international law, their legal bases are shown to be built on shifting sands.

The leading source of international law in the post Napoleonic era is "established precedent," or what may be more commonly referred to as "state practice." Chinese scholars typically ignore two important aspects of "state practice" in their arguments. First, the condition where territory is under the effective control of foreign armed forces is called "military occupation." International law fully recognizes that "Military occupation does not transfer sovereignty." Hence, military occupation is not equivalent to annexation. Second, international law in the post Napoleonic era has firmly established that there is only one mechanism by which territory can be transferred from one state to another: a legally ratified and binding treaty.

The content of many treaties can be carefully examined to reveal the established procedures by which territorial cession arrangements are made. For example, the Treaty of Shimonoseki, the very treaty in which Taiwan was transferred to Japanese sovereignty in the first place, includes a specific mention of that transfer in Article 2. The transfer is described in detail, as is the "beneficiary power" or "receiving country."

The Versailles Treaty ended World War I and was signed in Paris in 1919. In this treaty, territory transfers and new boundaries were specifically spelled out. All territorial transfers were described explicitly, with both the surrendering power and beneficiary being specifically referenced at all points in the document.

The Treaty of Guadelupe-Hidalgo was concluded between the United States and Mexico when the former had already occupied a significant amount of territory of the latter in a war. This war was begun in April - May 1846 when Mexican troops and US troops came into conflict regarding the demarcation of the Texas-Mexico boundary. As of early 1848, Mexico was outnumbered militarily and many of its large cities were occupied, while at the same time it was also faced with internal political divisions. It had little choice but to make peace on any terms. In the treaty, which came into force on July 4, 1848, Mexican territory that was transferred to the United States was specifically delineated. US military troops still present in Mexican territory returned to the USA.

The 1898 Treaty of Paris was drafted to end the Spanish-American War. At the conclusion of the war, the U.S. physically occupied Puerto Rico, the Philippines, Guam, and Cuba, all Spanish colonies at the onset of the war. This treaty is very useful in pointing out the power of the mechanism to transfer territory from one state to another. On the one hand, the transfer of the Puerto Rico, the Philippines and Guam to American sovereignty is specifically mentioned in the treaty. However, there is no such mention of Cuba being designated as being US territory.

Consequently, Cuba remained under the jurisdiction of the United States Military Government (USMG), since the United States of America is clearly the (principal) occupying power of the treaty. When Cuba's self-formed civil government was ready to assume governance, Cuba was granted independence, effective May 20, 1902. Contrastingly, Puerto Rico, Guam, and the Philippines remained as unincorporated US territories.

Japan completely defeated Russia in the Russo-Japanese War of 1904-1905. Japan already occupied territory that it was granted by the Treaty of Portsmouth (N.H.) in 1905. However, all of the territories to be transferred as well as the beneficiary (Japan) are specifically mentioned in the document, although some self-styled "legal experts" might advance various arguments based on the concept of "dominion" to say that such details were not entirely necessary at that point.

The above examples illustrate the situations of territorial cessions as the result of war, however there have also been many cessions during peacetime, and the following are well known examples: Louisiana (1803), Florida (1821), Gadsden Purchase (1853), Alaska (1867), Virgin Islands (1917).

Other examples can be referenced from the historical record, however the point should be sufficiently clear that the territory can only be transferred from one state to another via the specifications of a treaty.

Contrastingly, in the last 200 years of world history no examples are to be found where the international community has recognized the legal transfer of territory between states based on surrender documents, press releases, or related certification, records, manuscripts, communiques, etc.

IV.  Legal Implications for China's Claim on Taiwan

The content of the proclamations of Cairo and Potsdam are properly regarded as unfulfilled wartime commitments. Three allies announced their plans to give Taiwan to China following the war, but these "statements of intention" were never formalized in a peace treaty. It must be remembered that there were dozens of countries in the anti-Japan alliance. Three, no matter their size and importance, have no legal authority to make decisions of this nature which can then at some later date be somehow interpreted as legally binding on the entire alliance.

The Instrument of Surrender is a little closer because it is the first document that is accepted by Japan, the legal sovereign of Taiwan since 1895. However, it was only signed by military commanders of two countries, and had no provisions for ratification because it was technically no more than a cease-fire agreement.

We must not forget that there was a treaty which was concluded to end World War II in the Pacific. That is the San Francisco Peace Treaty. Chinese government officials and scholars like to say that since they didn't sign it, that treaty can have no effect on Chinese territorial claims on Taiwan. A more enlightened view would be to say that with the coming into force of the San Francisco Treaty, Chinese territorial claims on Taiwan have become null and void. It is also important to note that, as explained above, strong arguments can be made that neither the ROC nor the PRC had legal standing to sign the treaty.

The signing ceremonies were held in September 1951, in San Francisco, California. The treaty was signed by Japan and nearly 48 Allied Powers. It then went through the ratification process for each of the signatory powers before it came into effect in 1952. As such, it is the highest ranking document of international law regarding the disposition of Taiwan after the close of fighting in WWII. However, the Chinese KMT in Taiwan has always insisted that its own interpretation of history and legal arrangements was correct, and hence prevented the San Francisco Treaty from even being presented in school textbooks in Taiwan for over fifty years.

As a result San Francisco Treaty, Japan surrendered her sovereign claim over Taiwan. In other words, Taiwan was sovereign Japanese territory until this treaty came into force on April 28, 1952, and there was no "Taiwan Retrocession Day" in the Fall of 1945. Careful examination of the treaty shows that there are absolutely no provisions whatsoever for Taiwan being transferred to China, a clause deemed absolutely necessary by public international law to effectuate the transfer of territorial sovereignty.

In light of the above mentioned treaty arrangements, it should be abundantly clear that there is no legitimacy to the claim by China (Beijing) or the Chinese KMT (Taipei) that the territorial sovereignty of Taiwan was handed over to China at any time during the 1930s, 1940s, or 1950s.

There is still one more postscript to add, and it concerns the Treaty of Taipei between the ROC and Japan. Importantly, that treaty came into force on August 5, 1952, over three months after Japan had already given up sovereignty over Taiwan. Hence, there is absolutely no legal argument that can be made for Japan designating a disposition of sovereignty over a territory it had already given up in international treaty some three months previously.

In Taiwan, when the Japanese troops surrendered, the military occupation of Taiwan began. Some scholars point to the date of October 25, 1945, in Taipei, Taiwan, other scholars prefer the earlier date of Sept. 2, 1945, aboard the USS Missouri. Regardless of the date chosen, international law specifies that "Military occupation does not transfer sovereignty." Hence, under international law, the surrender ceremonies cannot be interpreted to signify a transfer of Taiwan's territorial sovereignty to China.