Salvadoran President Salvador Sanchez Ceren met with his Chinese counterpart, Xi Jinping, in Beijing yesterday, just months after the small Central American nation broke its diplomatic ties with Taiwan. The state visit comes one day before that of the president of the Dominican Republic, whose country also switched allegiances from Taiwan to China this year.

El Salvador and the Dominican Republic are among a growing number of countries that have cut ties with Taiwan in favor of resuming or establishing relations with China. Only 17 mainly small, developing countries now recognize Taiwan as a sovereign nation. Taiwan split from mainland China during a civil war in 1949, and Beijing has been steadily ratcheting up diplomatic and economic pressure since Taiwanese President Tsai Ing-wen took office in 2016.

Beijing's aggressiveness is largely driven by Tsai's refusal to endorse Beijing's "one-China principle," which maintains that Taiwan is part of China and that the Communist Party-ruled administration in Beijing is China's sole legitimate government.

Taiwan has long been a wedge between China and the United States, which has formal relations with Beijing but maintains robust unofficial military and diplomatic links with the island. Washington's de facto ambassador to Taiwan, Brent Christensen, said Wednesday that the U.S. would be opposed to "unilateral attempts to change the status quo" in Taiwan — a reference to increasing Chinese military intimidation.

China's wooing of Taiwan's allies in what the U.S. considers its backyard has rung alarm bells in Washington. The U.S. pulled out its diplomatic envoys last month from El Salvador, Panama and the Dominican Republic after those countries cut ties with Taiwan.