In one of history’s most shocking electoral upsets, Republican presidential nominee, Donald Trump, pulled off a decisive victory against his Democratic rival, Hillary Clinton. It was an outcome that defied practically all leading pundits and polls, putting into jeopardy the credibility of established media outlets and experts.

Though Clinton clinched more popular votes, Trump pierced through the Rust Belts and shattered the “blue wall” of Democratic dominance in one swing state after the other.

While it is too early to judge the merits and impact of a Trump administration, the immediate effect has been less than encouraging.

As post-election market fluctuation and nationwide anti-Trump protests demonstrate, the United States is a deeply polarised nation haunted by political uncertainty, which will certainly have a cascading effect on the rest of the world.

The US’ troubles at home will undoubtedly put into question its global commitments, particularly in key strategic theatres such as Asia. Moreover, Trump’s abject lack of political experience, divisive and often offensive rhetoric, and neo-isolationist philosophy will test Washington’s leadership in Asia like never before.

In contrast, China is likely to be seen as a relative rock of stability and bastion of mature leadership by a growing number of countries.

The shocker

Conversations with senior policymakers and analysts across the region suggest that Clinton was by far the preferred candidate in Asia, with the notable exception of China. As one of the architects of the Pivot to Asia policy, she oversaw deeper engagement with allies and rivals across the region.

During her tenure as Secretary of State, Clinton managed to normalise relations between Washington and Hanoi, consolidate relations with the democratising regime in Myanmar, and lay the ground for a deepened American military footprint in archipelagic Southeast Asia, particularly the Philippines and Singapore.

There was also greater engagement with the Association of Southeast Asian Nations (ASEAN) as a whole, as Washington appointed an ambassador to the regional body and studiously deployed senior policymakers, including outgoing President Barack Obama, to regional fora.

His 'America first' philosophy, coupled with his 'Make America Great Again' campaign slogan, suggests his preference for a more transactional, introverted foreign policy, which puts America's short-term interests ahead of the international liberal order.

In stark contrast, neither Trump nor his core team of advisers exhibit similar credentials or inspire much confidence. Trump, a billionaire businessman, has had no relevant diplomatic engagement with Asia. Much of his exposure to the region is based on pure business deals.

So far, Trump’s roster of advisers includes loyal friends and supporters, namely former governor Chris Christie, who is overseeing the transition team, former House speaker Newt Gingrich and former mayor Rudy Giuliani. But there are indications that Washington insiders are considering joining in.

The neo-isolationist

Aside from his lack of relevant experience, Trump’s rhetoric has also been a source of deep concern across the region. Throughout decades, in one interview after the other, Trump has consistently advocated a mercantilist conception of American global interest.

His “America first” philosophy, coupled with his “Make America Great Again” campaign slogan, suggests his preference for a more transactional, introverted foreign policy, which puts America’s short-term interests ahead of the international liberal order.

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This is precisely why he has repeatedly questioned Washington’s long-standing military commitments in both Asia and Europe, which have benefited from decades of US security umbrella.

He has threatened to withdraw American military support from vulnerable allies, ranging from the Baltic States which confront a Russian threat to South Korea which faces a volatile North Korea, unless they provide strategic “tribute” and fulfil their respective “obligations”.

No wonder then, shortly after his election victory, Seoul convened an emergency National Security Council meeting to assess risks of a potential American disengagement from the region. Strategic anxiety also permeates halls of power in Tokyo, Manila, Canberra and other traditional allied nations.

Not too dissimilar from the George W Bush administration, Trump has expressed more preference for unilateral assertion of American military muscle, particularly in the South China Sea, rather than harnessing regional institutions, international law and multilateral diplomacy.

Grand bargains

He seems to be more concerned with striking grand bargains with major powers, particularly Russia, than engaging with smaller nations and mobilising allies for preservation of public international goods.

Trump’s anti-trade rhetoric, which has transformed the (white) working class into his core constituency, also doesn’t bode well for the US’ economic engagement with the region.

He has opposed both existing (North America Free Trade Agreement) and proposed (Transpacific Partnership Agreement) regional commercial arrangements, which are crucial to the US’ strategic influence and economic wellbeing.

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His plans to impose heavy tariffs on trading partners in Asia, introduce “extreme vetting” on immigrants, and scrap the TPP agreement will heavily undermine the US’ leadership in the region.

Trump’s threat to overturn Obamacare, the Illegal Immigration Act, and other key legacies of his predecessor will surely provoke a backlash at home, further deepening America’s internal polarisation.

The president-elect’s mercurial temperament, incendiary rhetoric, and often-contradictory policy remarks have simply compounded a profound sense of uncertainty over the US’ role in the region in the coming years.

After all, it takes more than a gracious, reassuring victory speech for Trump to restore and harness regional trust in America and its commitment to the Asian strategic order.

He will have to dramatically distance his actual policy from his campaign rhetoric, sign up credible foreign policy advisers, constantly reiterate Washington’s commitment to regional alliances and the broader strategic order, and propose a positive-sum economic initiative, which will deepen, not reduce, trade and investment linkages in the Asia-Pacific theatre.

Otherwise, Trump’s presidency could very well mark the end of “American exceptionalism”, or any credible claim to such.

Richard Javad Heydarian is a specialist in Asian geopolitical/economic affairs and author of Asia’s New Battlefield: The USA, China, and the Struggle for the Western Pacific.

The views expressed in this article are the author’s own and do not necessarily reflect Al Jazeera’s editorial policy.