From war towards peace and peace towards war. This is how relations across the Taiwan Strait have evolved over the past 40 years. Efforts to seek peace have instead culminated in a greater threat of war.

Beijing’s “Message to compatriots in Taiwan” on January 1, 1979 is seen by many as having ushered in a new era after decades of hostility. The policy statement not only declared an end to Beijing’s routine artillery bombardment of Taipei-controlled islands, it marked a shift in its basic approach to Taiwan – from one of “liberation” (which implies the use of force) to one of “peaceful unification”.

However, a speech by Chinese President Xi Jinping on January 2 to mark the 40th anniversary of that message has been widely interpreted as opening the door to an eventual war.

Editorials across the world ran with headlines such as “Will China go to war over Taiwan?” and “Is Taiwan’s military really ready to take on China?”.

In his speech, Xi appeared to redefine the 1992 consensus – an unofficial agreement reached that year between representatives of Beijing and Taipei that there is only “one China”, but each side may have its own interpretation of what constitutes “China”.

He exhorted Taiwan to accept it “must and will be” unified with the mainland under Beijing’s concept of “one country, two systems”, which is overwhelmingly unpopular in Taiwan.

The speech prompted a rarely seen unity in parties across Taiwan’s political spectrum. Leaders of the ruling – and independence-leaning – Democratic Progressive Party, including President Tsai Ing-wen, rejected Xi’s suggestion, as did the main opposition party – the Beijing-friendly Kuomintang or KMT – and three other opposition parties.

The current and former KMT leaders Wu Den-yi and Ma Ying-jeou also took issue with Xi’s speech. Ma, who held a historic meeting with Xi in 2015, said in a radio interview there was no market for “one country, two systems” in Taiwan. Ma, during his presidency from 2008 to 2016, implemented a “three nos” policy – no reunification, no independence and no war.

A survey, taken between December 27 and 28 last year, found 81.2 per cent of Taiwanese could not accept the 1992 consensus. Another survey published last August by National Chengchi University found the vast majority of Taiwanese wanted to maintain their own identity, with only 3 per cent of respondents wanting unification now.

China has a lot to celebrate in 2019, but it also has old wounds to heal

The 1992 consensus laid the political foundation for talks between Beijing and the KMT, which was in power at the time it was agreed. It does this by acknowledging the dispute and by maintaining an ambiguity that allows the two sides to communicate. In redefining it, Xi may have closed the door on talks with the KMT should it be voted back into power in the 2020 presidential elections.

Successive Chinese leaders have sought to reunify Taiwan with the mainland but none have been as impatient as Xi, who has described the endeavour as an “inevitable requirement” for his politically ambitious programme of “national rejuvenation”.

Xi has said the “problem” cannot be put off for another generation and has called on the military to be prepared to fight “bloody battles” for every “single inch” of its territory.

Despite increasing exchanges in trade, investment, culture and people, the disagreement over sovereignty threatens an indefinite delay in negotiating the political issue.

Xi’s speech appears to reflect a loss of faith in Beijing at the prospect of a peaceful resolution. Beijing once assumed the Taiwanese would eventually decide to reunite with the mainland.

The Taiwanese, too, may have lost faith – they once widely forecast that communist rule would collapse after the mainland’s capitalist market reform, with the KMT insisting reunification would take place only under a democratic system.

The KMT’s election win in Taiwan has nothing to do with Beijing

Neither forecast has come to pass. The mainland’s communist regime survived the worldwide collapse of socialism in the early 1990s and seems to have become only more robust under an increasingly authoritarian government. And in Taiwan, separatist sentiments have grown stronger as a result of the island’s rush to embrace free democracy.

Now Xi has revived a civil war strategy by declaring the inevitability of reunification and threatening that “separatist” sentiments or foreign intervention will be met with force.

The reality that 40 years of endeavour have not narrowed the political gap in the 180km-wide strait, but widened it. Indeed, it is now the world’s most dangerous flashpoint for conflict.

As the door to talks closes, the door to war opens.

Cary Huang, a senior writer with the South China Morning Post, has been a China affairs columnist since the 1990s