Democrats in Taiwan and their supporters overseas were delighted with the re-election of President Tsai Ing-wen last week.

Tsai crushed the opposition candidate, Kaohsiung Mayor Han Kuo-yu, to claim a second four-year term. Equally important, her Democratic Progressive Party (DPP) retained control of the Legislative Yuan, even though it lost several seats in the assembly.

Celebrations were restrained, however, and with good reason: The DPP win was not just a defeat for the opposition Kuomintang, but also for Beijing. It will force the Chinese leadership to reassess its policy toward the island, and also Hong Kong. The results may not be to those Democrats’ liking.

Tsai soundly defeated Han, receiving 57.13 percent of the votes to his 38.61 percent. Especially satisfying for Tsai was the 8.17 million votes she won, nearly 10 percent more than the previous record count, the 7.23 million claimed by KMT candidate Ma Ying-jeou in the 2008 ballot.

Victory was especially sweet as a little over a year ago she was on the ropes. The DPP had been crushed in local elections in 2018, losing seven of 13 cities and counties it held, and its share of the vote plunged from 56 percent in the 2016 presidential race to 39 percent. With Tsai’s popularity falling to 24 percent in December 2018, senior members of her party called on her to abandon hopes of a second term and let a more popular politician head the ticket.

Her fortunes revived on the back of escalating protests in Hong Kong and the fears they engendered among Taiwanese regarding the threat posed by China. The mass protests that broke out across the special administrative region, the heavy-handed response and the indifference to the calls for accountability convinced Taiwan’s voters that closer ties with the mainland would jeopardize the island’s hard-won democracy.

For them, “the one country, two systems” model developed for Hong Kong that was supposed to entice the island into eventual unification with the mainland was a fraud. “We reject the ‘one country, two systems’ proposed by (Chinese President) Xi Jinping,” Tsai said during her campaign. “We value the lifestyle of democracy, and we defend our sovereignty.” Or, more bluntly, “Hong Kong today, Taiwan tomorrow.”

Rather than acknowledge the spread of a Taiwanese identity — an outgrowth of the island’s extraordinary economic and political accomplishments, and a repudiation of the Chinese identity that Beijing seeks to promote among residents — the Chinese government insists that voters were tricked, cheated and intimidated.

Beijing flatly dismissed charges that its policies might have been responsible for the electoral rebuke. Instead, it blamed “dark forces from outside” that it claimed manipulated the election. China’s official Xinhua News Agency charged that “Western external political forces” openly intervened “to contain mainland China and prevent the two sides from getting closer to each other, and supported Tsai Ing-wen.”

Foreign interference and deluded voters are predicates for more aggressive actions to produce Beijing’s desired results. Its bottom line is unyielding: Cross-strait relations are an internal affair of concern only to residents of the mainland and the island, and unification remains the only possible outcome. “Taiwan independence,” reported Xinhua, “goes against the tide of history, and it is a path to nowhere.”

If restraint — which is how Beijing sees its actions in Hong Kong — did not sway Taiwan’s voters, then there is little reason to continue that line. That is why many now fear a truly repressive response to continuing protests in the city.

Equally troubling is the prospect of growing impatience among the Chinese leadership at the failure to make progress on cross-strait relations. Despite a checkered first term, economic difficulties (worsened in no small part by mainland efforts to punish Tsai and her DPP government), and intensifying efforts to isolate Taiwan internationally — by resuming the diplomatic war in which China entices the handful of governments that recognize Taiwan to switch diplomatic recognition to China, and blocking Taipei from entering multilateral forums — Tsai was re-elected, and with a mandate. (Voter turnout in last week’s ballot reached 75 percent, nearly 10 percent higher than the last presidential election four years ago.)

Xi has consistently stated his determination to reunify the island with the mainland and there is concern that he may be forced to show some progress toward that goal. Tsai’s refusal to acknowledge not only the viability of the “one country, two systems” model but also the “1992 consensus,” in which leaders from Taiwan and China reportedly agreed that there is only one China on both sides of the Taiwan Strait, has infuriated Beijing and would serve as the justification for action on China’s part. After her win, Tsai emphasized her “commitment to peaceful, stable cross-strait relations” based on parity between the two sides and dialogue. That is not enough for Beijing.

The primary obstacle to Chinese aggression against Taiwan is the U.S. commitment to the island’s defense. Under President Donald Trump, ties between Taipei and Washington have become even closer and some see a golden age in the relationship. At the same time, however, Taiwanese quietly voice a fear that Trump sees Taiwan as a card to play as he deals with China. If the U.S.-China relationship recovers — as it may after this week’s trade deal — or Trump wants to do his “friend” Xi a favor, that commitment could become more tenuous.

Taiwan’s relations with Japan are shaped by similar concerns. While much of the work is done quietly and without fanfare, Tokyo is Taipei’s most important partner, after Washington. Signs of a thaw in Japan’s relations with China, and the prospect of a “fifth communique” — a document that provides the framework for the bilateral relationship, and which would include some mention of Taiwan — during Xi’s state visit to Tokyo this year, worry Taiwanese. They fear that Tokyo too may be recalibrating relations with China, and that Taiwan will suffer as a result.

In both cases, a genuine shift, one that would threaten Taiwan, is extremely unlikely. The danger is not necessarily abandonment, however, but statements by the governments in Washington and Tokyo that encourage a belief in Beijing that it has more latitude to act. The risk of miscalculation is real. One more reason why victory celebrations in Taiwan last week were quieter than expected.

Brad Glosserman is deputy director and a visiting professor at the Center for Rule Making Strategies at Tama University and a senior adviser (nonresident) at Pacific Forum. He is the author of “Peak Japan: The End of Great Ambitions.”