Lai’s victory at the polls in January marked a narrow but unprecedented win for the Democratic Progressive Party (DPP).

Since Taiwan transitioned to democracy in 1996, the DPP and its more Beijing-friendly rival the Kuomintang (KMT) have switched power every eight years, but Lai’s victory broke with that tradition as the DPP won a third term in office.

Tsai’s vice president, Lai will have big shoes to fill.

During her eight years in office, Tsai dramatically raised Taiwan’s profile abroad while treading a fine line around its disputed political status, lest it upset China or the United States.

Tsai’s tenure coincided with a new wave of Taiwanese nationalism, as well as a vision of Taiwan as distinct from China despite its deep historical and cultural ties. She also oversaw major changes for the island, including the legalisation of same-sex marriage in 2019 and the introduction of same-sex adoption in 2022.

Lai is expected to continue steering the East Asian democracy largely in the same direction, a point he hammered home during the campaign.

“William Lai has spent the past two and half years trying to convince the world he is going to be a Tsai Ing-Wen 2.0 figure,” said Lev Nachman, a political scientist at Taiwan’s National Chengchi University.

“There’s reason to believe him, even though there is a lot of scepticism about what he in his heart of hearts truly feels, there’s enough structural constraints that are going to stop him from being able to do anything drastic,” he said

Lai’s cabinet, named in April, includes several former members of the Tsai administration while his charismatic vice president, Hsiao Bi-khim, 52, was once Taiwan’s top official in the US and is also aligned with the former president.

At home, Lai is likely to be constrained by a hung parliament after the DPP lost its small parliamentary majority to the KMT. Abroad, he faces a challenge from the US presidential election in November, whose outcome will dictate regional stability more than anything Lai can do as president, according to Nachman.

The US is Taiwan’s chief security guarantor, but it does not want to see a proxy war break out in the Taiwan Strait between itself, Taiwan and China. Neither does Taiwan, where most people support maintaining the island’s ongoing “status quo.”

The term is deliberately vague, but it encompasses the viewpoint that Taiwan is already de facto independent despite its lack of formal diplomatic recognition. The island, officially known as the Republic of China, is only recognised by a handful of countries, primarily in the Pacific and the Caribbean.

Taiwan is claimed by China’s Communist Party (CCP), which has long threatened to bring it into the fold by force if necessary. Everyday Taiwanese reject that goal, but most do not wish to make a formal declaration of independence because they fear it would lead to a certain war with Beijing.

‘Worker for independence’ or ‘troublemaker’

As innocuous as the term may sound, supporting the “status quo” marks a major ideological shift for Lai, who once upon a time described himself as a “pragmatic worker for Taiwan independence.”

Originally trained as a doctor, Lai was compelled to enter politics in 1996 in the wake of the Third Strait Crisis, according to his official biography. The incident saw China conduct missile tests in the Taiwan Strait for several months between 1995 and 1996 as Taiwan geared up for its first direct presidential elections.

He later served as a legislator, mayor and premier of Taiwan, before he made an unsuccessful bid to challenge Tsai as the DPP presidential candidate ahead of her 2020 re-election. Instead, he became vice president after Tsai won a second term in the presidential office in a landslide.

“If you think about Lai now in comparison to the past, you just couldn’t imagine that he is the same person,” said Sanho Chung, a PhD candidate in political science at the University of Arizona whose work includes Taiwan. “If you look at Lai as a mayor back in the day or as a lawmaker, he was kind of radical.”

Both Chung and Nachman said they expected a relatively muted response from Beijing ahead of inauguration day, despite a flare-up earlier this month around Taiwan’s outlying island of Kinmen when more than a dozen Chinese vessels entered the island’s restricted waters to carry out “maritime exercises” on May 9.

Beijing has continued to send military aircraft into Taiwan’s air defence identification zone, an area of land and sea monitored by the military, but the numbers are consistent with past activity, according to defence analyst Ben Lewis, who tracks Beijing’s activity.

Their predictions contrast with Beijing’s belligerent response to a visit by then-US Speaker of the House of Representatives Nancy Pelosi to Taiwan in August 2022, when it staged several days of military exercises in the Taiwan Strait.

Beijing repeated the move a year later when Tsai met Kevin McCarthy, another former House speaker, during an unofficial stopover in California on her way home from meeting allies in Central America.

NCCU’s Nachman said China may keep a lower profile as it appears to be attempting to semi-normalise relations with the KMT.

Beijing does not recognise Taiwan’s government and has cut off official communication since the DPP’s victory in 2016, but it has kept up unofficial contact touch with the KMT over the past eight years.

The KMT and the CCP have a relationship dating back to the 1920s and fought against each other during different stages of the Chinese Civil War, culminating in the KMT’s retreat to Taiwan in the late 1940s.

Since the 1990s, however, the relationship between the two parties has warmed.

Former KMT President Ma Ying-jeou has made two trips to mainland China over the past two years, becoming the first Taiwanese leader to visit since the end of the Chinese Civil War.

KMT members have also made private visits to China in recent years, including this year and last.

In contrast, Beijing still considers members of the DPP as dangerous “separatists”.

Not least the man set to lead the island for the next four years. For China, Lai is not only a “separatist” but a “troublemaker”.