The visit of US House Speaker Nancy Pelosi to Taiwan on Tuesday drew severe criticism from Beijing, which claims the self-ruled island as its own territory.

The following are significant events in US-China-Taiwan relations:

1949 – Mao Zedong’s communists win control in Beijing after a civil war with Chiang Kai-Kuomintang shek’s (KMT) nationalists. The KMT-led government withdraws to Taiwan, breaking off touch with mainland China.

1950 – Taiwan becomes an ally of the United States, which is at war with China in Korea. The United States deploys a fleet in the Taiwan Strait to protect its ally from possible attack from the mainland.

1954-1955 – The First Taiwan Strait Crisis: Beijing launches artillery attacks on some Taiwan-controlled outlying islands off China’s southeastern coast. Taipei loses its control of some islands and moves remaining forces and residents to Taiwan.

Chen Shui-bian is elected President of Taiwan in 2000, marking the Democratic Progressive Party’s (DPP) first term in office. The DPP advocates Taiwanese sovereignty and formal independence.

In March 2005, Beijing passes an anti-independence measure that makes Taiwanese secession illegal. For the first time since 1949, leaders of Taiwan’s main opposition KMT and the Communist Party of China will meet in April.

May 2008 – KMT-supported President Ma Ying-jeou, a proponent of deeper ties with China, takes office and sets aside political differences with China to negotiate partnerships ranging from tourism to commercial aviation.

March 2018 – Trump signs legislation encouraging the United States to send top officials to Taiwan to meet with Taiwanese colleagues, anger China once more.

September 2018 – The US State Department permits the sale to Taiwan of replacement parts for F-16 fighter planes and other military aircraft for up to $330 million, prompting China to warn that it jeopardizes bilateral cooperation.

July 2022 – US President Joe Biden and Chinese President Xi Jinping conduct a two-hour phone chat in which Biden emphasizes that “US policy has not changed and that the US strongly opposes unilateral moves to alter the status quo or threaten peace and stability across the Taiwan Strait.”