One of the major unintended consequences of Philippine President Rodrigo Duterte's foreign policy is the fracturing of an emerging regional alliance in the South China Sea. By cozying up to China and turning away from allies in Southeast Asia, the Filipino leader has almost single-handedly undermined resistance within the Association of Southeast Asian Nations to Beijing's expansionary moves in regional waters.
The most immediate casualty is the once-close cooperation between two states with the most at stake -- the Philippines and Vietnam.
By downgrading the Philippines' military cooperation with the U.S., Duterte has also provided China more space to push its claims in the South China Sea, including at Vietnam's expense. In recent months, the Philippines has even begun to once again view Vietnam as more of a rival, rather than an ally, in these contested waters.
A recent shooting incident, which saw the Philippine Navy fatally wounding several Vietnamese fishermen, highlights growing tensions between the two neighbors over illegal fishing. The rapid depletion of stocks in northern portions of the South China Sea, largely driven by large-scale Chinese commercial fishing, is expected to further compound the rivalry.
With key ASEAN claimant states pursuing divergent (if not conflicting) strategies in the South China Sea, China has been left in a stronger position to dominate adjacent waters to the detriment of its smaller neighbors. The upshot is a bitterly divided ASEAN, which has left Beijing as the undisputed victor in the ongoing scramble for maritime supremacy.
Business people are watching the evolving tensions keenly. China has consistently been a top-trading partner to the Philippines, with bilateral trade standing at around $17.646 billion (2015), a number that is expected to triple in the coming decade. Chinese investments in the Philippines in 2015 amounted to $1.4 billion. For the Philippines, commercial ties with Vietnam are of little importance in comparison.
A promising alliance
Just a year ago, the Philippines and Vietnam were viewed as de facto allies against China in the South China Sea. With Hanoi and Manila occupyingcontested land features in the Spratly islands, they both viewed Beijing as the major threat to their positions.
Through massive reclamation, and the deployment of advanced military assets to its artificially-created islands, China posed a direct challenge to the two Southeast Asian states' tenuous presence in the area.
Both Hanoi and Manila also detested what they saw as Beijing's continuous harassment of their fishing as well as energy exploration activities within their respective exclusive economic zones and continental shelves.
Eager to solicit maximum possible international assistance, the liberal democrats in Manila, then under President Benigno Aquino III (2010-2016), and communists in Hanoi, now increasingly influenced by reformers, shed their lingering ideological as well as historical differences in favor of establishing a common front.
Forging a de facto alliance, they jointly sought to nudge ASEAN toward a more robust position on China's activities in the South China Sea disputes.
The two Southeast Asian countries also welcomed stronger defense cooperation with external powers, particularly the U.S. and Japan, which offered maritime security assistance to China's beleaguered rivals.
They also strengthened bilateral strategic cooperation. Hanoi supported the Aquino administration's unprecedented decision to take China to an international tribunal at The Hague, and, for the first time in history, it deployed its two flagship warshipson a good will visit to Manila in 2014.
In 2015, the two sides formalized their emerging alliance by signing a strategic partnership agreement, pledging to deepen not only theireconomic ties, but also defense and diplomatic cooperation, particularly in the South China Sea.
All fall down
In particular, Vietnam has been interested in leveraging the Philippines' legal victory against China , where an international tribunal nullified the bulk of China's expansive claim over almost the entirety of the South China Sea basin..
The two countries hoped to encourage other major ASEAN actors, especially Indonesia and Malaysia, to also joint the emerging informal alliance against China's expansionary objectives .
The mid-2016 election of Duterte, however, radically altered the strategic equation. The new Filipino leader immediately announced his decision to effectively "set aside" the arbitration award in favor of improved strategic and economic ties with China. He also cancelled plans for patrols as well as ongoing joint-military exercises with the Washington in the South China Sea.
This provided China much-needed strategic space to expand its military footprint in the area with virtual impunity. To the chagrin of Hanoi, Duterte also used his chairmanship of the ASEAN to push back against earlier efforts, including by the Philippine government, to mobilize regional states against China's maritime assertiveness.
This year even saw the Philippines and Vietnam clash over the ASEAN's joint statement on the South China Sea, mainly thanks to Duterte's decision to shield China against criticism. A perturbed
More recently, the two neighbors have found themselves at loggerheads over allegedly illegal fishing by Vietnamese citizens. In September, the death of two Vietnamese fishermen and injury of several others at the hands of the Philippine Navy almost ignited a diplomatic crisis between the two former allies.
To the dismay of Vietnam, the Philippines' maritime forces have begun to take an increasingly aggressive position to deter illegal fishermen entering Philippine waters, particularly the Vietnamese. In contrast, Chinese fishermen, who are closely guarded by Chinese coast guard forces, have been left largely to their own devices by Philippine law enforcers.
Meanwhile, prominent figures in the Philippines have begun to portray Vietnam, instead of China, as the major threat in the South China Sea. They argue that Hanoi) is the most aggressive claimant state in the area, since it controls up to 29 land features in the Spratlys, more than three times that of the Philippines (8-9) and China (7),
To be fair, China has managed to charm much of Southeast Asia by offering development aid as well as large-scale infrastructure investment under the aegis of the Maritime Silk Road Initiative and the Asian Infrastructure Investment Bank. Not just the Philippines but other ASEAN maritime claimant states such as Malaysia and Brunei have shown deep interest in maintaining warm ties with Beijing despite the tensions.
But it remains to be seen whether China's eye-catching regional economic initiatives will translate into sustained . Meanwhile, China's huge trade surplus, including with the Philippines and Vietnam, remains a source of contention.
Moreover, there is no guarantee that diplomatic engagement with China will tame its behavior in in the South China Sea. Quite the opposite: The demise of cooperation between Manila and Hanoi has opened the way for Beijing to tighten its grip on one of the world's most strategic waterways.
Richard Heydarian is a Manila-based academic and author of, most recently, "The Rise of Duterte: A Populist Revolt Against Elite Democracy."