Former Philippine president Rodrigo Duterte was arrested on March 11 in Manila after a trip to Hong Kong. He was quickly flown to stand trial at International Criminal Court in The Hague, where he faces charges of crimes against humanity stemming from his “war on drugs.”
In allowing the arrest to proceed, current President Ferdinand “Bongbong” Marcos Jr. struck a decisive blow against the Duterte family, which includes his own vice president, Sara Duterte, who is now under investigation for corruption and facing an impeachment trial. Formerly allies in the 2022 election, the Marcos and Duterte political dynasties remain at odds. The drama continued through the May 2025 mid-term elections, where Marcos-aligned candidates underperformed expectations, while Rodrigo Duterte himself won his old mayoral seat in absentia.
This dispute, far from merely a domestic battle over political control, has serious implications for Philippine foreign policy, as well as for other states that have avoided choosing sides in the ongoing China-U.S. competition. The Dutertes are pro-China, while Marcos has embraced the Philippines’ traditional alliance with the United States.
What was a primarily domestic contest in Manila has now adopted features of foreign policy polarization as the two camps jockey for superpower alignment. The broader lesson for China-U.S. great power competition is that domestic foreign policy polarization is increasingly common in Indo-Pacific swing states. This means that the United States needs to grapple with how its foreign policy choices impact the internal political landscape in key allies and partners.
Duterte Vs. Marcos
In Philippine politics, the most important political families incubate powerful regional networks of influence and patronage to jockey for power, all the while cutting deals and making and breaking alliances. For a brief moment in 2022, the two leading dynasties, the Marcoses and Dutertes, set aside their differences and appeared aligned – that is, until they were in power, when simmering tensions boiled over.
Rodrigo Duterte, the founder of his dynasty, remains one of the most controversial (and popular) figures in Philippine politics. Duterte waged a brutal drug war at home, overseeing the extrajudicial killings of at least 6,000 people, which is now the subject of his ICC case. His populist style nevertheless proved highly popular in the Philippines. Because Duterte was term limited, his daughter, Sara Duterte, formed an alliance with Marcos to jointly contest the 2022 presidential election as vice president and president respectively.
Marcos is the son of the former strongman president, Ferdinand Marcos Sr., who was overthrown in 1986 during the People Power Revolution. Despite their overthrow and exile, the Marcos family’s patronage networks, wealth, and prestige remained formidable, especially in the north. Marcos Jr. eventually fully rehabilitated his family’s image with his resounding win in 2022. At that time, the Duterte-Marcos alliance signaled potential warning signs for the United States if outgoing President Duterte’s pro-China, anti-U.S. policies remained in place.
However, personal rivalry, foreign policy disputes, and a struggle over control of the administration soon spilled out into the open. From 2023 onwards, the public dispute continued to escalate, leading to an infamous livestream by Vice President Sara Duterte, during which she threatened to have Marcos murdered. Marcos’ allies subsequently impeached Sara, with the trial expected to occur in July. With her father undergoing his own trial in The Hague, Sara now faces an uncertain political future.
The result of the Philippines’ May 2025 midterm elections suggest that the political situation remains in flux. Marcos-aligned candidates underperformed, but the Dutertes did not run away with it either. Liberal opposition candidates also experienced a resurgence. The Duterte dynasty’s popularity seemingly remains undented and perhaps even rejuvenated.
Who ultimately prevails in this domestic contest has serious implications for the Philippines’ foreign policy and U.S. competition with China.
The Philippines Between the United States and China
Under President Rodrigo Duterte’s 2016-22 tenure, the Philippines veered sharply from its traditionally close alliance with the United States. Although he did not abandon the treaty alliance with the U.S., Duterte publicly questioned it and wooed China. Going against traditionally anti-China, pro-U.S. public sentiment in the Philippines, Duterte relaxed Philippine opposition to China’s transgressions in the South China Sea and attempted to garner Chinese investment. He also made public statements against the United States, even threatening to end the Visiting Forces Agreement and halt bilateral military exercises, which displeased the pro-U.S. security establishment in Manila
Unfortunately for Duterte, however, China did not hold up its end of the bargain. Beijing continued to pressure the Philippines in the South China Sea and its promised foreign direct investment proved underwhelming. By 2021, the nationalist Duterte administration had little choice but to work more closely with the United States, even if he would have preferred to align with Beijing.
Upon his election, Marcos undid any remaining pro-Beijing stance in Philippine foreign policy, thus jump-starting a new golden age in the Philippines-U.S. alliance. In 2023, the United States and the Philippines announced the expansion of the Enhanced Defense Cooperation Agreement (EDCA), which will prove critical to U.S. force posture south of Taiwan. The following year, the United States hosted Japan and the Philippines in Washington in the first trilateral summit between the three countries. That meeting resulted in the announcement of key initiatives, including the Luzon Economic Corridor in the Philippines. Both the Biden and Trump administrations publicly affirmed the two nations’ Mutual Defense Treaty.
Despite the tumult triggered by President Donald Trump’s imposition of a 17 percent tariff on the Philippines last month, bilateral ties remain strong, especially compared to other Southeast Asian states. U.S. Secretary of Defense Pete Hegseth visited Manila in March, resulting in continued American commitments to Philippine defense against China. The United States also soon approved the sale of 20 F-16 fighters to Manila. Ahead of the joint Balikatan exercises in April and May 2025, the Philippines described it as a “full battle test… a rehearsal for our defense.”
Marcos is also pursuing closer relations with other U.S. allies and partners. He has signed a reciprocal access agreement with Tokyo, upgraded ties with Australia, and purchased BrahMos cruise missiles from India, which will enhance deterrence vis-a-vis China. In a sign of the Philippines’ emerging role at the center of the U.S. alliance network, Manila embraced a new quadrilateral security arrangement, “the Squad,” and welcomed the U.S. deployment of intermediate-range ballistic missiles on its territory.
China-Philippines relations, in contrast, are now at a nadir. Marcos stood up to China in the South China Sea and implored the other Association of Southeast Asian Nations (ASEAN) states to act more swiftly in addressing the maritime crisis. Clearly angry, China escalated its gray zone coercion against the Philippines in the South China Sea, deploying its coast guard with water cannons and ramming tactics against Philippine vessels near disputed land features. Beijing hopes to pressure the Philippines to withdraw from the disputed Second Thomas Shoal. Risky maritime incidents are now a common occurrence.
China also regularly disparages the Philippine government, accusing it of increasing maritime tensions, interfering in Taiwan, and, in a new revelation, violating a “gentlemen’s agreement” forged with Rodrigo Duterte in 2016 regarding the South China Sea dispute. Recent court cases exposed the extent of China’s intelligence operations in the Philippines, and pro-China (and pro-Duterte) disinformation remains rampant online.
Alarmingly, China’s President Xi Jinping hosted Rodrigo Duterte in Beijing in 2023, sending a clear message of support to China’s friend in Manila. Chinese media reported that Xi said during the meeting that, when president, “Duterte resolutely made the strategic choice of improving relations with China.” Beijing’s preference for the Duterte days could not be clearer. Indeed, China’s Foreign Ministry spokesperson took time during its daily briefing to implicitly criticize Duterte’s March 11 ICC arrest. It also felt the need to explicitly deny that Duterte had been in Hong Kong seeking asylum.
Domestic Politics in Indo-Pacific “Swing States”
The two most powerful families in the Philippines have clear preferences for the United States and China, and whoever wins out will determine the future of Philippine alignment. But, from a 50,000-foot view, there are wider lessons regarding non-aligned states in the Indo-Pacific that hedge between the United States and China.
Domestic politics in “swing states” has serious implications for China-U.S. competition. In traditional realist international relations theory, states are treated as unitary actors pursuing their rationally determined national interests. In Southeast Asia, this manifests as “hedging,” where states pursue multi-alignment and attempt to avoid over-exposure to any one great power while simultaneously working for the best deal possible for their interests. In today’s great power competition, the relative lack of ideological battle lines akin to the Soviet-U.S. Cold War and emergent multipolarity renders alignment more fluid, hence opening more space for hedging.
However, individual actors and factions within domestic political systems matter in how governments define and redefine what constitutes their “national” interests. In a new era of great power competition, how and when states hedge depends upon their specific governing coalition.
As great power competition worsens, domestic actors with ideological affinity, material interests, or a desire for external backing may face incentives to align more or less closely with rival great powers, especially in key swing states in the Global South. Understanding this will be crucial for U.S. success in the new cold war with China.
Despite her pending impeachment trial, Sara Duterte remains the frontrunner in the upcoming 2028 Philippines presidential election, which Marcos cannot run in due to term limits. If Sara were to avoid an impeachment conviction and successfully run for the presidency, we can expect that U.S. access to EDCA sites, and perhaps even the alliance itself, could be in jeopardy. A victory by the Marcos faction or the liberals, on the other hand, would likely secure continued pro-U.S. alignment.
When foreign policy becomes a serious issue of contention among rival political camps, it is likely to draw in the United States and China, which also face incentives to support and reward their aligned partners. This can be characterized as “cold war-ization.” Despite an overall trend toward multipolarity, in the Indo-Pacific, the two leading poles – the United States together with its allies and China – are configured more like a bipolar system and will therefore likely demand closer alignment from their partners (including across key sectors).
This phenomenon of polarized foreign policies in “swing states” in the Indo-Pacific is not unique to the Philippines. In Myanmar’s civil war, the pro-democracy National Unity Government received substantial support from the United States during the Biden administration, thus incurring Chinese wrath and increased backing for the ruling military government. Elections in the Pacific have recently witnessed political actors adopting either pro-China or pro-U.S./pro-Taiwan stances. Similarly, New Delhi and Beijing have struggled for influence in the Maldives and Sri Lanka as competing factions in both countries look for external support.
Yet, foreign policy polarization is not inevitable. In the Philippines’ neighboring democracy Indonesia, which had an important election last year, there’s no sign of it despite an equally personalistic political environment. Meanwhile, in one-party state Vietnam, the Communist Party remains committed to its foreign policy hedging, despite substantial leadership turnover.
Crucially, in states where it does occur, “foreign policy polarization” does not necessarily imply polarized publics. Indeed, the Filipino population remains ardently pro-American and anti-China. Instead, it is foreign policy polarization among the elite that control policymaking that matters. The nature of hedging and the relatively non-ideological form of China-U.S. competition also means that these polarizing elite factions or parties can at times moderate or switch sides if the domestic or geopolitical incentives shift. The Dutertes remain deeply committed to China, but in Sri Lanka, President Anura Kumara Dissanayake has seemingly reached out to New Delhi despite his party’s traditional ties to Beijing. He could also always swing back.
From an immediate policy perspective, the best thing the United States can do is to avoid playing into Beijing’s hands. That means it should work closely with the Marcos government to fulfill its promises, uphold the Philippines-U.S. Mutual Defense Treaty, back up Manila in the South China Sea, and encourage the U.S. private sector to invest in the country. However, setting tariffs on Manila at 17 percent, as suggested in the initial “Liberation Day” announcement, could devastate Philippine growth and render Marcos’ pro-U.S. policies more difficult to justify. Taking action that embarrasses Marcos or weakens the Philippines’ economic performance will simply help the Dutertes and Beijing.
In the future, Washington will need to watch domestic politics in its allies closely – while also understanding that hedging will remain the driving force of foreign policy for most Indo-Pacific states.