US President Joe Biden meets with Philippine President Ferdinand Marcos, Jr., on the sidelines of the UN General Assembly in New York City on September 22, 2022. (Photo: Mandel Ngan / AFP)

The US-Philippine Alliance: Shared Interests and Subtle Nuances


The US National Security Strategy (NSS) identifies some shared interests between Washington and Manila. However, there are nuances in the strategic calculus of the allies when it comes to two key potential flashpoints in the region: Taiwan and the South China Sea.

In October 2022, the Biden administration released its National Security Strategy (NSS) which identified the Indo-Pacific region as the “epicenter of 21st century geopolitics,” with China as the only competitor with both the intent and capability to reshape the international order. To advance its goal of a “free, open, prosperous, and secure international order,” Washington reaffirmed its commitments to treaty allies and pledged to “modernise these alliances.” This might appear to underscore the convergence in views between the United States (U.S.) and the Philippines, particularly on hot spots such as Taiwan and the South China Sea. But there are subtle differences in perspectives between the two allies that warrant some examination.

While typically viewed as separate issue-areas, Taiwan and the South China Sea are very much related. After all, the two are closely connected by geography as part of the First Island Chain. Conceived by American diplomat John Foster Dulles, the chain is used to illustrate an offensive and defensive perimeter running from the Japanese home islands down to Taiwan, the Philippines and Indonesia. As a concept, it sought to contain Chinese military expansion in the Pacific. From the U.S. perspective, close relationships with countries in the First Island Chain reinforce America’s strategic foothold in the region amid talks of its relative decline. From China’s perspective, it is surrounded by America’s allies and partners which prevent Beijing from having a military presence commensurate to its status as an emerging superpower. If China establishes preeminence in the South China Sea or successfully reunifies Taiwan with the mainland, Beijing will be free to look outward and shift the regional balance of power to its favour.

The NSS articulates the convergence of interests between the U.S. and its allies, including the Philippines. Indeed, Washington and Manila share the broad security interest of ensuring a favourable balance of power for both countries, as well as constraining China’s maritime expansionism. In the case of Taiwan, the allies prefer the preservation of the status quo in cross-strait relations.

However, there are nuances when it comes to the strategic calculus of both countries regarding the two hot spots. For the U.S., its primary interest in the South China Sea is to ensure “freedom of the seas and build shared regional support for open access to the South China Sea.” The Philippines’ primary interests are more insular: its territorial integrity, national sovereignty, and maritime rights, which are similar to those of other Southeast Asian claimant states.

While the last two U.S. administrations and a 2019 legislation provided public assurance of military support, some measure of uncertainty may be expected. This is not to suggest that Manila should terminate the 71-year old Mutual Defense Treaty (MDT) with Washington. On the contrary, the allies need to prepare coordinated responses for various scenarios.

With respect to Taiwan, there is a subtle difference between both countries on the “One-China” principle as propagated by the Washington (which is conceived as the “One China” policy in the eyes of Beijing). Both the Philippines and the US recognise the People’s Republic of China as the sole government of China. However, while the Philippines “fully understands and respects” Beijing’s position that Taiwan is part of China, the U.S. merely “acknowledges”, but does not recognise, that position.

The convergence and divergence of the allies’ interests and policies have two implications for their security relationship.  

First, the Philippines will need to walk a delicate balancing act on the Taiwan issue. Even if Manila wants to be insulated from cross-strait tensions and possible conflict, Manila needs to balance its One-China principle, and the U.S.’ growing imperative to muster allies for a Taiwan invasion contingency (only the Bashi Channel separates the Philippines and Taiwan). Washington, in particular, may request access to Philippine military bases. If the Philippines grants this, it must do so while being committed to its One-China principle at the diplomatic level. At the same time, it is highly doubtful that the distinction would matter to China, who would look at American boots on the ground as a threatening forward-posture that adds to U.S. deterrence against an invasion of Taiwan.   

Second, the Philippines needs to prepare for contingencies in the South China Sea. Cognisant of the dynamics of alliance abandonment and entrapment, there is imperative for the Philippines to prepare for scenarios in which US military support is not forthcoming. While the last two US administrations and a 2019 legislation provided public assurance of military support, some measure of uncertainty may be expected. This is not to suggest that Manila should terminate the 71-year old Mutual Defense Treaty (MDT) with Washington. On the contrary, the allies need to prepare coordinated responses for various scenarios.

Despite the challenges, the NSS notes an opportunity for the US and its allies and partners to shape China’s external environment “in a way that influences (its) behavior”. The full implementation of the Enhanced Defense Cooperation Agreement (EDCA), which provides an increased rotational presence of US forces in the Philippines, would allow Manila to complement the NSS’ “integrated deterrence” concept. There is an imperative for Manila and Washington to issue a statement stating that the provisions of EDCA will continue beyond 2024. While the agreement provides that it will “continue in force automatically” after its initial ten year term, the statement would nevertheless send a message to opponents of EDCA — both foreign and domestic — that the allies will continue working with each other in the pursuit of their shared interests.

Capacity-building is another important component of the alliance. Two days after the NSS was released, the U.S. Embassy in Manila announced that US$100 million would be granted to the Philippines as part of Washington’s foreign military financing program. To promote interoperability, the allies had also agreed to conduct 496 defence and security engagements in 2023. This marks an increase compared to the 461 activities in 2022. These initiatives are important in order to strengthen Manila’s capability to manage security challenges.

The NSS warns that the world is “now at an inflection point” and that the coming “decade will be decisive.” A contested security environment is not necessarily preferable for small powers like the Philippines. This behooves Manila to work closely with Washington in promoting an effective alliance management through which they would advance their shared interests while carefully navigating the nuances in their interests and policies on Taiwan and the South China Sea.


Mico A. Galang is a lecturer at the Department of Political Science, University of Santo Tomas (Manila, Philippines).