Fifty years ago this August, the Association of South-east Asian Nations was born from the desire to maintain the region's neutrality in a world increasingly dominated by the two Cold War superpowers.
In Asean's founding document, the Bangkok Declaration, each of the five original member states pledged to "ensure their stability and security from external interference in any form or manifestation". Four years later, those same states devoted an entire agreement to the principle of non-interference, affirming a collective determination to "secure the recognition of, and respect for, South-east Asia as a zone of peace, freedom and neutrality".
Over the succeeding half-century, on the shoulders of those foundational documents and the principles they embody, Asean has grown into an organisation essential to the security and stability of East Asia. However, that may be coming to an end.
This month, as was announced last September, Philippine President Rodrigo Duterte will begin his term as Asean chairman. Despite campaign promises to "ride a jet ski" through disputed islands in the South China Sea, Mr Duterte has closely aligned himself and his nation with the People's Republic of China since taking office.
During a visit to Beijing last October, Mr Duterte announced that "there are three of us against the world - China, Philippines and Russia", and refused to discuss the arbitral tribunal's ruling in favour of the Philippines on maritime sovereignty issues.
Likewise, in a December speech in Manila, he proposed a joint Sino-Philippine oil exploration in the disputed Scarborough Shoal and seemed to acknowledge the futility of challenging Beijing's ongoing militarisation of the waters.
In the background, vast sums of money have flowed from China to the Philippines, with US$24 billion (S$34.5 billion) in Chinese investment and aid pledged in October and prospects for much larger amounts in the near future.
Given Mr Duterte's well-established track record of acting on his own extreme rhetoric, there is legitimate reason to fear that Mr Duterte will not only make hollow the Asean commitment to neutrality by repeating the self-interested decisions of Cambodia and Laos, but will also go further and use his role to drag Asean - however unwilling - into Beijing's orbit and away from its traditional role as a bulwark against foreign influence.
Given that China's ongoing assertiveness in the South China Sea is arguably the most pressing issue facing Asean today, cause for concern should be self-evident.
As maritime sovereignty in the South China Sea is an issue of "foreign interference in any form or manifestation" that involves four different member states, under Article 32 of the Asean Charter, Mr Duterte, as chair, has an obligation to "ensure an effective and timely response" to this issue in line with the organisation's guiding principles. While neutrality does not necessarily entail a condemnation of China's activities, it does require the articulation of a common position, something that, if recent precedent is any guide, chairman Duterte will likely be unable to do.
Twice in the past five years, Asean's commitment to neutrality has been derailed by chairs willing to sacrifice the principles of Asean for the economic self-interest of their own nations. And in both of those instances, the similarities to Mr Duterte's Philippines are striking.
In 2012, during Cambodia's term as chair, Asean failed to issue a joint communique for the first time in its history solely because Cambodia refused to reference the South China Sea issue. Phnom Penh's rationale was obvious - Cambodia had accepted over US$10 billion in aid from Beijing, with a further US$13 billion on the horizon.
As one unnamed diplomat told The New York Times, "China bought the chair, simple as that".
Similarly, last June, Laos - then serving as Asean chair - withdrew a statement of Asean foreign ministers expressing "serious concerns" regarding Chinese expansion in the South China Sea. According to contemporary press accounts, Beijing aggressively lobbied Vientiane to do so, and Laos readily acquiesced, unwilling to upset a nation that had, months earlier, announced US$31 billion in investments along the Sino-Laotian border.
There is no indication that Mr Duterte, whose nation is to receive equally large sums of investment from Beijing, will be any more resilient or autonomous than the leaders of Cambodia or Laos when South China Sea issues inevitably arise. As described earlier, the Philippines' pecuniary interests have become increasingly tied to Beijing, and as Mr Duterte continues to shun the West over criticisms of his human rights record, Manila's dependence on China - and thus the comparisons to Cambodia and Laos, in terms of receptiveness to Beijing's pressure - will only increase.
However, what should make Mr Duterte's chairmanship especially frightening to those with a vested interest in Asean is his public image. Over the past six months, he has embraced the identity of a Sinophile without remorse.
In a November speech in Davao City, Mr Duterte exclaimed that he "will be the first to join" any Sino-Russian "new order", and before the Great Hall of the People in Beijing in October, he explained that a China-Russia-Philippines alliance was "the only way" - statements that should be particularly alarming given that he is now chairman of an organisation designed to ensure and protect non-interference and neutrality in South-east Asia.
Given Mr Duterte's well-established track record of acting on his own extreme rhetoric, there is legitimate reason to fear that Mr Duterte will not only make hollow the Asean commitment to neutrality by repeating the self-interested decisions of Cambodia and Laos, but will also go further and use his role to drag Asean - however unwilling - into Beijing's orbit and away from its traditional role as a bulwark against foreign influence. After all, one of his other duties under Article 32 is to strengthen and promote relations between Asean and external partners.
Thus, the combination of Mr Duterte's close ties to Beijing and his domineering braggadocio poses a unique threat to Asean on its 50th anniversary.
Hopefully, the Philippine leader's rhetoric is just that, and the former Davao mayor recognises the difference between being leader of a single nation and chairman of a regional organisation tasked with preserving peace and stability.
If not, a formidable challenge may lie ahead for other member states if Asean is to remain true to its principles in its next half-century.
•The writer is a Juris Doctor candidate at the University of Virginia School of Law and executive editor of the Virginia Journal of International Law.
•SEA View is a weekly column on South-east Asian affairs.