Of all of the recent trips to Asia by US presidents, and of all of the current president’s overseas tours, Donald Trump’s visit to Asia could be the most crucial, as it could shape the future of US leadership in the region.

It may be an overstatement to say that Trump’s trip is his last chance to revitalize America’s regional leadership, as the five-nation visit is the president’s first to the region. However, it is probably right to argue that should he fail to demonstrate meaningfully his commitment to the United States’ regional alliances and partnerships during this 12-day trip that started on Friday, it would further damage America’s already weakened position in this dynamic, complex and vital region.

As is often said, if a week is a long time in politics, then a year is an eternity. This is just as true in international politics, especially in the Trump era. The global political landscape has changed radically – almost inverted – since his election as president of the United States about a year ago.

Only a year ago the prospect that the US would turn into a fierce critic of the global liberal economic and political order it had shaped and led for seven decades and that China could become its ardent advocate was almost inconceivable.

Such an unreal reversal of roles is now happening, however. And Trump’s largely unexpected victory in last November’s US presidential election was a defining reason behind this shift.

With an “America First” doctrine, a nativist, protectionist and isolationist policy aimed at satisfying populist sentiments at home, the new president has abandoned his country’s postwar role as the leader of the liberal order based on free trade, international agreements, the rule of law and democratic values.

Perceiving that Trump is ceding the United States’ long-held global leadership mantle, over the past year, China’s Xi Jinping has made remarkable steps toward filling that void.

In January, just three days before Trump’s swearing-in as America’s 45th president, Xi made a headline-grabbing address – the first by a Chinese leader – at the World Economic Forum. In that keynote speech at the WEF in Davos, Switzerland, regarded as the spiritual home of capitalism, the Chinese president denounced isolationism and protectionism and presented his highly controlled nation as a robust defender of free trade and an open economy.

Speaking at the United Nations Office at Geneva a day later, he went even further, urging the world to “uphold the authority of the international rule of law” and, again, positioned the People’s Republic of China as a responsible and law-biding player in that order.

At the recent Congress of the Communist Party of China, which elevated him to the almost sacred status of Mao Zedong, the PRC’s founder, Xi hailed China as a “mighty force” in the world and a role model for political and economic development. He even asserted that his country’s political system “is a great creation” that offers “a new choice for other countries.”

Little more than a year ago, hardly anybody could have imagined that the authoritarian leader of a communist nation would make such bold statements at such important international and domestic forums. Some might have even laughed at such a prospect.

But all of this is no longer laughable. Undoubtedly, Trump’s numerous missteps and mishaps, both at home and abroad, have emboldened the Chinese leadership’s confidence.

Since taking office, Trump has pulled the US out of key international agreements, such as the Paris climate accord and the Iran nuclear deal. His posture has greatly alarmed many countries, including Washington’s closest allies, and tremendously damaged America’s global leadership.

Undoubtedly, Trump’s numerous missteps and mishaps, both at home and abroad, have emboldened the Chinese leadership’s confidence

In contrast, Xi Jinping has proactively and assertively portrayed himself as a great international statesman and his country as a reliable, even indispensable, global leader by publicly stating that the rising superpower is committed to honoring those international treaties.

Perhaps nowhere in the world is America’s recession and China’s assertion felt more strongly than in Asia.

The Trump White House’s inward-turning stance is exemplified by his decision to abandon the Trans-Pacific Partnership (TPP). His withdrawal from this huge US-led trade deal, which would also have had other far-reaching geopolitical implications, is seen by many as an abandonment of America’s traditional regional leadership role not only in trade but in other vital areas, such as security.

In addition, Trump has threatened to terminate his country’s free-trade agreement with South Korea, a key strategic ally.

All of this has puzzled and rattled America’s important Asian partners and allies.

In contrast, with the TPP collapsing, the PRC, which was excluded from the 12-member accord, has pushed to conclude the Regional Comprehensive Economic Partnership (RCEP), a rival trade pact of 16 East and Southeast Asian countries.

In May, Beijing inaugurated its Belt and Road Initiative, a global trillion-dollar infrastructure and trade plan. Though the grandiose project won’t generate huge win-win opportunities for all participating countries as Beijing preaches, almost all nations in the region have now signed up to join it.

Yet while worried by Trump’s “America First” foreign policy, many Asian countries are still hoping he could rethink his posture and continue US engagement with the region, especially in the areas of trade and security.

With perhaps a few exceptions such as Cambodia that have already fallen deeply into China’s orbit, almost all regional states still count on the world’s biggest economy and military to maintain regional prosperity and security.

Leaders from Japan, Australia, India, South Korea, Vietnam, Malaysia, Thailand and Singapore have already traveled to the Trump White House, with some of them making trade concessions, mainly because they wanted such a commitment of US engagement from Trump.

A recent Pew Research Center survey found that the US is still seen more positively than China in India, Japan, South Korea, the Philippines and Vietnam.

However, compared with previous years, America’s image in the world,  including many Asian countries, this year has significantly weakened while China’s favorability has considerably strengthened. In Australia, a key strategic US ally, and Indonesia, the United States now is less favored than China.

Again, Trump’s election and his subsequent policies have hugely contributed to this weakening of America’s global and regional image. If this trend continues, it is very likely that China will hold a competitive advantage in favorability over the US in the years to come.

Against this background, Trump’s trip to Japan, South Korea, China, Vietnam and the Philippines is a very high-stakes one. It could make or break America’s regional leadership.

If he clearly demonstrates that the US remains deeply committed to the region, by offering concrete and positive measures to strengthen economic and security ties with Asian countries, bilaterally or multilaterally, that will greatly help restore trust in American leadership.

In contrast, if he fails to do that – or, worse, continues to harden America’s already damaged position in the region – many countries, notably small, but geo-strategically important, nations such as Vietnam and Singapore, may move away from Washington and toward Beijing.

At the moment, for both economic and security reasons, they still seek to maintain balanced ties with the world’s two superpowers. Still, any combative move by Trump will tip the balance in China’s favor, especially if Beijing pursues a benign posture toward its neighbors as it has done of late.

Before the recent Party Congress, the Chinese leadership sought to repair strained ties with Vietnam and Singapore. Just days before Trump begins his Asian trip, Beijing unexpectedly decided to mend relations with South Korea after a year-long standoff over Seoul’s decision to install Terminal High Altitude Area Defense (THAAD), a US-operated anti-missile shield, on its soil.

If this is not tactical behavior but a genuine shift in Beijing’s policy, Trump must work hard during his current trip to convince America’s Asian partners and allies that the US under his leadership remains a sine qua non of the region’s peace and prosperity.