Is Donald Trump turning out to be a paper tiger? China’s rulers might be forgiven for thinking so after the US president performed a U-turn on Taiwan, but the shift did not come out of the blue.

Trump’s approach to a range of key international issues has softened significantly since he took office, suggesting a lurch towards conformity and away from disruption. His acceptance of the One China policy, under which Washington does not challenge Beijing’s claim to what it deems a breakaway province, was a stunning reversal, contradicting previous suggestions he would pursue closer ties with Taiwan.

The Chinese appear to have successfully applied considerable diplomatic pressure, insisting on a reaffirmation of existing US policy on Taiwan as a precondition for discussing issues closer to Trump’s heart, such as bilateral trade. Beijing made clear Taiwan was a red line. President Xi Jinping called Trump’s bluff. Trump blinked first.

The idea that Trump is all talk has been slowly gaining ground since his inauguration last month, though it contains an element of wishful thinking. In his first week in office Trump and his inner circle tried hard to demonstrate they were honouring controversial campaign promises such as restricting immigration from Muslim-majority countries.

But there have been a string of unmistakeable, Taiwan-like foreign policy shifts on substance, reaching beyond mere questions of tone and style. One is Trump’s revised attitude to expanded Israeli settlements. Another is his pledge to move the US embassy to Jerusalem from Tel Aviv. Israel’s government, led by Benjamin Netanyahu, plainly believed Trump’s election meant a green light for unrestricted new building. But in an interview published on Friday by the Israel Hayom newspaper, Trump performed a volte-face, saying settlement construction was “not helpful” in advancing the moribund peace process. Trump also hedged on his embassy pledge. “It’s not an easy decision. It’s been discussed for so many years. No one wants to make this decision,” he said.

Trump’s inflammatory campaign pledges on other sensitive foreign policy are also being watered down. His warning to Japan and South Korea, Washington’s two most important Asian allies, that they should not rely so much on the US for their defence seems to have been forgotten. James Mattis, the new US defence secretary, spent last week in Seoul and Tokyo offering reassurances that the US was as reliable a friend as ever. In fact, Mattis went further, specifically promising Japan that the US military would defend the disputed Senkaku islands in the South China Sea from any Chinese encroachment. He also confirmed the deployment of a new missile defence system in South Korea.

Trump’s view on Nato has also been almost miraculously transformed. Before taking office he claimed it was obsolete. He has since told Nato’s secretary general that he is “strongly committed” to the alliance, a message repeated by Mattis and the CIA director, Mike Pompeo, during a visit to Turkey. Trump gave Britain’s Theresa May a similar assurance at the White House.

Following a pattern, Trump ignominiously backed down after a row with Australia’s prime minister, Malcolm Turnbull, over a refugee resettlement deal. After Turnbull stood up to him, the “bully-in-chief”, as Australian commentators dubbed him, caved in. The deal is going ahead.

And despite vowing to shake up the United Nations and withdraw US funding, Trump’s new UN ambassador, Nikki Haley, lost no time in using the security council platform to clarify his administration’s attitude to Russia. Haley pinned the blame on Russia for a recent surge of violence in eastern Ukraine and warned sanctions would not be lifted until Moscow reversed its annexation of Crimea. “We do want to better our relations with Russia. However, the dire situation in eastern Ukraine is one that demands clear and strong condemnation of Russian actions,” Haley said.

The US condemnation punctured the narrative, popular among Trump’s opponents, that he is naively seeking an unconditional “reset” with Vladimir Putin, Russia’s president. Improved relations remain Trump’s goal. He continues to heap praise on Putin, a leader whose ruthlessness and killer instinct he says he respects.

But on Russia’s involvement in Syria and Afghanistan, on the perceived threat it poses to eastern Europe, and on the problems arising from Russian-linked cyber and information warfare, Trump’s approach has turned cautious of late. It is gradually moving into alignment with that of his predecessor Barack Obama and Nato.

Even on Iran, Trump’s bark has so far proved far worse than his bite. He reviles Tehran as the world capital of state-sponsored terrorism. His national security adviser, Michael Flynn, recently threatened unspecified military action after a rogue missile test. But Trump seems to have heeded advice from May and others that he cannot simply tear up the 2015 nuclear deal with Iran, as he had vowed to do. The hot air in the White House has cooled, pending what it calls a “strategic review” of America’s Iran policy. Obama could not have put it better.

Is Trump learning on the job? Or is he just a bully who backs off when he encounters resistance? Given his volatility and unpredictability, it is possible he could reverse himself again on key policies, reverting to his more radical and destabilising ideas. So far, the responsibilities of office, and the complexities of the issues, do seem to be weighing more heavily on Trump’s outlook. Other national leaders and more experienced advisers like Mattis are exerting influence. And Trump, in office, is coming up against a sobering reality that faces all American leaders sooner or later: the limits of presidential power.