Philippine President Rodrigo Duterte makes a "fist bump", his May presidential elections campaign gesture, with soldiers during a visit at Capinpin military camp in Tanay, Rizal.Erik de Castro / Reuters

When Rodrigo Duterte, president of the Philippines, stood before an audience of Chinese businessmen at a trade function in the Great Hall of the People on October 20 in Beijing, he promised a “separation” from the United States. It wasn't clear exactly what he meant, but he implied it would entail dropping the United States—his country’s third-largest trade partner, security guarantor, and former colonizer—in favor of an ill-defined three-way alliance with China and Russia. This was consistent with his pledges to draw back U.S.-Filipino military relations by suspending joint military exercises, re-examining other security agreements, and drawing closer with China.  

Perhaps the most puzzling aspect of Duterte’s staunch anti-Americanism is how starkly it diverges from public opinion. In recent years, polls have shown that Filipinos love the United States even more than Americans do. Other surveys show that most Filipinos distrust regional rival China, and overwhelmingly trust the United States. Much of this amity stems from the long, shared history between the two countries, dating back to the end of the Spanish-American War in 1898 when the United States replaced Spain as the the ruling colonial power, and to World War II, when U.S. forces liberated the Philippines from Japanese occupation and granted the country’s independence in 1946. After World War II, the United States and the Philippines agreed to a mutual defense treaty, giving the United States access to military bases in the country, including the massive Subic naval base.

In the modern era, American troops have assisted the Filipino government in battling Islamist insurgents. The U.S. government has also taken the lead in humanitarian assistance, providing over $37 million after Hurricane Yolanda in 2013, which killed over 10,000 Filipinos. This year, the U.S. navy began conducting joint patrols with the Filipino navy to challenge China’s claims in the South China Sea (Duterte has since suspended those exercises). And on the economic and cultural side, roughly half of the Philippines’s middle and upper classes have relatives in the United States. Remittances from the United States—around $10 billion a year—are a major driver of the Philippines’s economy, according to Steven Rood, the the Asia Foundation’s country representative for the Philippines.  

But whether these warm feelings actually matter when it comes to formal alliances between sovereign states is unclear. Duterte is currently enjoying a 76 percent approval rating. As long as he remains popular, Filipino affection for the United States, in of itself, won’t be enough to save the alliance between the countries.

Dominic Tierney, a political scientist at Swarthmore College and Atlantic contributing editor, argued that there is no iron law that countries whose citizens like each other will be allies—although it usually helps. The United States is most popular in Canada and Britain, two countries that support U.S. military operations around the world. But Tierney also added that “You can’t tease out a law of history that says popular support guarantees alliance decisions.” In the Middle East and Central Asia, the United States has often struck enduring alliances with regimes whose publics broadly dislike the United States—such as Egypt and Jordan—while antagonizing regimes like Iran's whose citizens view the United States more warmly.

Of course, the Philippines, unlike those other countries, is a functioning democracy. If Filipinos don’t like their country’s foreign policy, they can try to change it using avenues unavailable to Iranians. As Tierney pointed out, one example of a relatively democratic country that punished its leader for switching alliances is Ukraine. Following the Maidan Square protests of 2014, Ukrainian citizens furious with President Viktor Yanukovych’s move to scrap a bid for European Union membership in favor of a trade pact with Russia succeeded in ousting him and returning their country to its prior foreign policy orientation.

Still: It’s unclear whether the Philippines would ever follow suit. While Duterte hopes to source loans from the China-led Asian Infrastructure Investment Bank (AIIB), he has not proposed any alliance with China nearly as far-reaching or detailed as the Ukrainian pact with Russia that sparked the Maidan. And besides, it’s far from clear whether ordinary Filipinos would be inclined to challenge Duterte over his foreign policy. “Most people, including Filipinos, don’t pay attention to foreign policy, so elites have considerable latitude,” Rood said.

There’s also the matter of Duterte’s popularity. “Duterte has a huge, passionate following, while the U.S. has a huge, passive following,” Richard Javad Heydarian, a political science professor at La Salle University in Manila, explained. Poorer Filipinos, especially those who, like Duterte, hail from the country’s underdeveloped south, feel that they finally have a decisive president who will improve their lives. “That is why Duterte can get away with it,” Heydarian added. No one is predicting pro-American rallies on the streets to challenge Duterte. Nor do they expect that his anti-American bluster will cut strongly against his popularity in a country that appreciates his nationalism.

That special brand of Dutertian nationalism diverges sharply with that of his predecessor, Benigno Aquino III, who made defending Filipino territorial sovereignty against China, with the backing of the United States, central to his foreign policy. But Duterte also has a personal grudge. When he was mayor of Davao City, he was denied a visa to visit the United States, which he believed was due to his brutal anti-drug campaign. He also still has unanswered questions over an accidental bombing in Davao City in 2002, allegedly caused by a U.S. citizen who left the country afterwards, evading prosecution, with the help of the FBI. The shadowy nature of the bombing and the supposed involvement of U.S. officials confirmed Duterte’s stereotypes of a superior, meddling America. Following the bombing, Duterte refused to give the U.S. military access to airports in the city.

In Duterte’s view, the United States continues to treat the Philippines as its “little brown brother,” in the words of Perfecto Yasay, Duterte’s anti-American foreign affairs secretary. To that end, it invents or exacerbates security problems against Islamist insurgents in the South, or against China in the South China Sea, to justify its military presence. In the world according to Duterte (and, more broadly, the Filipino left), the United States endangers, rather than preserves, Filipino sovereignty.  

But while Duterte’s vehement rhetoric is unprecedented, his presidency doesn’t mark the first time Filipinos have sought distance from the United States. In 1991, the Filipino senate passed a resolution forbidding American troops to be permanently stationed on the Philippines. In 2005, the Philippines and China announced a “golden age of partnership," which included a push by then-President Gloria Arroyo to increase military ties with China. Today, Arroyo advises Duterte on China policy. Malcolm Cook, a senior fellow at the Institute of South East Asian Studies Institute in Singapore, noted, however, that when it comes to ties with China, “Duterte’s taking it further” than Arroyo ever did. Still, as long as Duterte can frame his actions as part of a mission to preserve Filipino sovereignty, there’s reason to think the Filipino people, by and large, won’t object to drawing closer to China.

Far more worrying for Duterte is the prospect that his country’s powerful military and business groups, which maintain close ties to the United States, will turn against him. The United States is the Philippines’s largest source of foreign direct investment, especially in industries like electronics manufacturing and business-process outsourcing, which have contributed to the rapid expansion of the Filipino middle class. Investment into the Philippines has decreased by 41 percent since last June, and it isn’t clear whether the investment agreements Duterte inked in October with Chinese companies can reverse the trend, especially if nervous American investors start pulling out. The peso fell to a seven-year low against the dollar after Duterte’s anti-American comments and questioning of the rule of law. If Duterte ends up damaging the economy, business leaders could turn against him, as could a public that might suddenly connect his foreign policy views to worsening economic conditions in their own lives. Even then, it would not be Duterte’s rejection of the United States, but the overall decline of the economy, that would set Filipinos on edge.

And the military could pose just as big a risk as business interests. “No other country has a military as intertwined with and dependent on the U.S.,Heydarian said. In a recent op-ed, former President Fidel Ramos, a mentor to Duterte with close ties to the military, condemned Duterte’s mishandling of U.S.-Filipino relations, declaring that his leadership has been a “huge disappointment and let-down to many of us.”

Duterte is, most likely, listening. Threats of military intervention have long cast a shadow over Philippines politics. In 2001, the military withdrew support for unpopular then-President Joseph Estrada, hastening his downfall. As recently as last year, credible reports suggested that some elements of the military were plotting a coup against President Aquino. Duterte, for his part, visited 14 different military camps in the opening weeks of his presidency, and has promised to give each of the Philippines’s 120,000 soldiers new, Israeli-made Glock pistols. And in response to a growing chorus of criticism from politicians at home, five days after his call for separation from Washington, he clarified that the U.S.-Philippines “alliances are alive,” and assured Filipinos that there “should be no worry about changes of alliances."

Of course, any concerns Duterte may have about his support among the military were not enough to stop him, on his return from a recent trip to Japan, to say that he wanted to see all U.S. troops gone within the next two years—a position unlikely to be popular with the top brass.

In the end, perhaps the safest bet is that U.S.-Philippines military-to-military relations will be downgraded, but the alliance itself will remain intact. Washington can tolerate a thin-skinned ally who bites the hand that feeds him through crass invective and accusation, even as he makes overtures to its rivals. The United States has plenty of experience with touchy allies around the world, from Turkey’s President Recep Tayyip Erdogan, who accuses Washington of backing this summer’s failed coup attempt against him, or former Afghan President Hamid Karzai, who called Americans “demons” who “committed satanic acts that will never be forgiven.” If Duterte doesn’t follow through with his promise to expel the U.S. military from the Philippines, and the economic relationship remains more or less on track, U.S. policy makers may be to block out Duterte’s rhetoric.

Tierney applies Ruth Bader Ginsburg’s dictum on how to maintain a good marriage to how to maintain a good alliance: “It helps to sometimes be a little deaf.”

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