As speaker of the US House of Representatives, Nancy Pelosi is charged with a number of duties and responsibilities, with a strong commitment to law, including international law, and a deep sense of impartiality, including in diplomatic representation, being prominent among them. But by making a stopover in China's Taiwan during her tour of Asia which covered Singapore, Malaysia, the Republic of Korea and Japan earlier this month, Pelosi violated international norms as well as the principles on which Sino-US relations are based.

Her official stopover in Taiwan in a manner as if she was visiting a sovereign state, and therefore implicitly according a status as a separate political entity to the island, has pushed the US into a political quagmire for legal, diplomatic and moral reasons.

Yet US provocations have not ended with Pelosi's visit, because despite strong protests from China, a US lawmakers' delegation landed on the island on Sunday on a two-day visit. This no doubt will further worsen Sino-US ties.

The legal quagmire: In October 1971, the 26th Session of the United Nations General Assembly adopted Resolution 2758, which decided to "restore all its rights to the People's Republic of China 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".

The UN resolution made it clear that Taiwan's legal status was as a territory under sovereignty of the People's Republic of China. Altogether 181 sovereign states, including the United States, have recognized the UN resolution and established diplomatic relations with the People's Republic on the basis of the one-China principle.

The diplomatic quagmire: Based on the legal commitments, and following Resolution 2758, the three joint communiques the US has signed with China constitute the political foundation of Sino-US relations. Indeed, during former US president Richard Nixon's visit to China in 1972, Washington made a clear commitment in the Shanghai Communique that "the US acknowledges that all Chinese on either side of the Taiwan Strait maintain there is but 'One China' and that Taiwan is a part of China. The US Government does not challenge that position".

On Dec 15, 1978, just more than two weeks before diplomatic relations were formally established between the People's Republic of China and the US, the two governments issued the second joint communique, which states that the US and the People's Republic of China have agreed to recognize each other and to establish diplomatic relations as of Jan 1, 1979, and "The United States of America recognizes the Government of the People's Republic of China as the sole legal Government of China. Within this context, the people of the United States will maintain cultural, commercial, and other unofficial relations with the people of Taiwan".

On Aug 17, 1982, the then Ronald Reagan administration signed the third joint communique with the People's Republic of China which states that "the United States of America recognizes the Government of the People's Republic of China as the sole legal Government of China, and it acknowledges the Chinese position that there is but one China and Taiwan is part of China" and that "the United States Government... reiterates that it has no intention of infringing on Chinese sovereignty and territorial integrity, or interfering in China's internal affairs, or pursuing a policy of 'two Chinas' or 'one China, one Taiwan'".

Given the above facts, and the urgent need to put Sino-US relations back on track so as to strengthen cooperation to boost the global economy, fight climate change, maintain peace and stability in the Asia-Pacific region, denuclearize the Korean Peninsula, and end maritime and digital piracy, one cannot but wonder what Pelosi's visit to the island gained. The answer was provided by the Economist in its Aug 2 edition: Pelosi's trip to Taiwan highlights the US' incoherent strategy.

The moral quagmire: The visits of US officials to the island are gross violations of the US' commitments. More than 170 countries have backed China on its stance. The US House of Representatives, as part of the US government, is obliged to follow the one-China principle and prevent its members from engaging in any official capacity with China's Taiwan.

So Pelosi's visit to the island, in whatever form and under whatever pretext, is a major political provocation to China and an immoral reneging on the US' political commitment. In particular, the visit reflects the US' political inconsistencies, and is a blatant violation of the one-China principle and the three China-US joint communiques. Worse, Pelosi's visit has pushed the US into a (legal, diplomatic and moral) quagmire and cast a shadow on the future relations between the world's two largest economies. In short, Pelosi's political blunder has the potential of depriving us of a better future.

The author is an associate professor at, and associate dean of, the Institute for Research on Portuguese-speaking Countries, City University of Macau. The views don't necessarily reflect those of China Daily.

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