The United States signed a Mutual Defense Treaty with the Philippines in 1951, making a commitment to come to Manila’s aid if the Philippine armed forces, public vessels or aircraft are attacked. The treaty excludes the shoals and rocks of the South China Sea, specifically mentioning only help to defend the “metropolitan territory” of the Philippines and the “Pacific Area” — but the July ruling leaves the United States with an alliance security dilemma.
Specifically, the dilemma is how resolutely a state should commit to an ally and the cost this incurs with adversaries. A strong commitment can result in entrapment in an unwanted conflict with an alliance adversary, but a weak commitment engenders feelings of abandonment on the part of the ally and a weakened alliance. In this case, a stronger U.S. commitment to Manila angers Beijing, but a weaker commitment leaves Manila feeling unsupported.
Alliances leave both partners with less room to maneuver
The problem is that alliances can be costly. If the United States shows a strong commitment to the Philippines, there’s a risk of being drawn into an unwanted conflict with China. If the Philippines feels overly confident about the U.S. commitment to the alliance, Manila may be more intransigent in its relations with China — and more willing to engage in riskier behavior, which could lead to a militarized conflict in the South China Sea. The U.S.-Japan alliance and the Japan-China dispute over the Senkaku Islands in the East China Sea presents a similar alliance dilemma, but in this case Washington has clearly stated its support for Japan.
Conversely, if Manila doubts the U.S. commitment to the alliance, the Philippines may feel abandoned by the United States. But this might constrain any risky behavior by Manila and encourage compromise — and this would reduce Washington’s concerns about becoming trapped in a South China Sea conflict.
The United States has been reticent to militarily support the Philippines
Here’s how the U.S. willingness to support the Philippines militarily in its territorial dispute with China has been playing out:
1) In 2010, Secretary of State Hillary Clinton noted, “While the United States does not take sides on the competing territorial disputes over land features in the South China Sea, we believe claimants should pursue their territorial claims and accompanying rights to maritime space in accordance with the UN convention on the law of the sea.”
2) In 2011, Clinton did make a reference to U.S. treaty obligations when she underlined the U.S. commitment to the Philippines, saying, “We are making sure that our collective defense capabilities and communications infrastructure are operationally and materially capable of deterring provocation from the full spectrum of state and non-state actors.”
3) As tensions began to spike in 2012 over Scarborough Shoal, the State Department declared, “We are concerned by the increase in tensions in the South China Sea and are monitoring the situation closely. . . .The United States urges all parties to take steps to lower tensions in keeping with the spirit of the 1992 ASEAN Declaration on the South China Sea and the 2002 ASEAN-China Declaration on the Conduct of Parties in the South China Sea.”
Washington again showed a clear reluctance to invoke the mutual security treaty and risk being entrapped in a China-Philippines militarized conflict over rocks and shoals in the South China Sea. In 2012, a senior U.S. military official spoke frankly. He said, “I don’t think that we’d allow the U.S. to get dragged into a conflict over fish or over a rock. Having allies that we have defense treaties with, not allowing them to drag us into a situation over a rock dispute, is something I think we’re pretty all well-aligned on.”
Philippine officials view the alliance somewhat differently
The agreement enhances the defense cooperation between the Philippines and the United States and aids the Philippines in developing its defense capacities and strengthening its maritime domain awareness. The agreement allows the rotation of U.S. armed forces to the Philippines to facilitate the U.S. rebalance to the Asia-Pacific. But there is no mention of the South China Sea.
Nevertheless, the Philippines’ then-president, Benigno Aquino III, asserted in May 2016 that the United States “has to maintain . . . the confidence of one of its allies” and “would be obligated to take military action in the South China Sea if China moved to reclaim a hotly contested reef directly off the Philippine shore.”
Although no U.S. official has explicitly committed to come to the Philippines’ defense if it is embroiled in a militarized conflict over disputed islands, some analysts suggest that Washington should strengthen the alliance with the Philippines by making clear that the Mutual Defense Treaty includes features in the South China Sea.
The U.S. response to the July ruling has been low-key and cautious, taking no victory lap despite the welcome outcome of the tribunal. The ruling pleases the United States, especially because of its concerns over freedom of navigation in this strategic waterway. But some are unhappy with what they characterize as an “anemic” response and call for a more assertive policy by Washington.
So here is Washington’s strategic dilemma. The tribunal’s ruling provides Manila legal and political leverage to press for more resolute U.S. support if the Philippines seeks to enforce the tribunal’s decision by confronting the Chinese at Scarborough Shoal or other features occupied by China. But this is just what the United States does not want: being forced to take a stand and possibly becoming embroiled in a military conflict over a “rock dispute.”
If Washington makes a clearer commitment to Manila, does that encourage the Philippines to stand tall against China? In this scenario, it’s possible the United States would be at risk of becoming entrapped in a Philippines-China militarized conflict in the South China Sea. At the same time, a stronger U.S. commitment to the Philippines would do little for U.S.-China relations but may encourage Beijing to seek a compromise solution with the Philippines.
Research has shown that conditional deterrent alliances — which means only promising assistance in case of an attack — reduce the likelihood that a minor power allied to a major power will provoke a conflict. Mindful of Washington’s reluctance to get dragged into a military conflict with China, newly installed Philippine President Rodrigo Duterte has taken a conciliatory position, expressing a desire to seek negotiations with Beijing, despite the favorable decision by the tribunal.
Former Philippine president Fidel Ramos was dispatched to Hong Kong earlier this week to break the ice and hopefully set the state for negotiations. Although China rejected the tribunal’s decision, Beijing has also expressed a willingness to negotiate. Washington will welcome this because it reduces the chances of becoming entrapped in a Beijing-Manila conflict. But closer Philippines-China relations may introduce new tensions in the U.S.-Philippines alliance if it appears that Manila is distancing itself from Washington.