Recent developments have increased the impetus for the alliance’s renewal. Philippine President Ferdinand Marcos Jr has expressed concerns that a military battle between the United States and China over Taiwan will almost certainly entangle the Philippines. The highly contested grey zone of the South China Sea — an area in which China is making aggressive territorial claims and deploying military assets to disputed islands — is causing significant concern among neighbouring countries. These fears have escalated since the China–Philippines standoff at Scarborough Shoal in 2012.
In the context of China’s assertiveness, the United States has reiterated its commitment to the Philippines and its willingness to help defend the nation’s sovereignty in the South China Sea. The US–Philippines Mutual Defense Treaty, which was signed in 1951, serves as the foundation for this commitment, providing for the mutual defence of both countries in the event of an armed attack.
Given the rising geopolitical tensions between the United States and China, Marcos’s call to ‘[evolve] the alliance to make it more responsive to present and emerging challenges’ has been heeded by Manila and Washington. One example of this closer alignment between the two nations are efforts to modernise the US–Philippines alliance. In April 2023, Philippine National Defense Secretary Carlito Galvez and US Secretary of Defense Lloyd Austin discussed plans to operationalise four new Enhanced Defense Cooperation Agreement sites, deepening military interoperability between the United States and the Philippines.
The new Enhanced Defense Cooperation Agreement sites are also expected to support combined training, exercises and other operational activities between US and Philippine armed forces, enabling the countries to effectively respond to shared security challenges. It was made clear that the Enhanced Defense Cooperation Agreement is primarily about the Philippines’ interests, not Taiwan’s. The United States has allocated over US$82 million for projects in these locations, which also aims to support economic growth and job creation in local Philippine communities.
The two countries have made further commitments to building interoperability and cooperation in both conventional and unconventional domains, particularly for disaster relief and maritime security. This includes adopting a security roadmap to guide shared defence modernisation investments and inform the delivery of priority platforms over the next five to ten years.
The US and Philippine defence secretaries recognised the value of collaborating closely with like-minded countries such as Japan, members of the AUKUS trilateral security partnership and ASEAN. The potential to strengthen operational cooperation with partners such as Japan and Australia was recognised, which could include observation and participation in trilateral and multilateral exercises.
Both the United States and the Philippines backed the ASEAN Outlook on the Indo-Pacific in April 2023 and stressed the need for regional alliances and arrangements in maintaining ASEAN’s prominence. The secretaries agreed on the necessity of expanding economic and security cooperation with other Southeast Asian partners through a variety of measures, including joint training and capacity building. But ASEAN’s ineffectiveness over the years, particularly in solving the Myanmar crisis, has increased the likelihood that the Philippines will concentrate more on improving bilateral relations with the United States.
The Balikatan military exercises — held annually between the United States and the Philippines to improve combined planning, combat readiness and interoperability — reinforce the Philippines’ commitment to integrating the US security alliance into its broader regional network. The most recent exercise was the most advanced in history, involving 12,200 US forces, 5400 Filipino forces and a diverse set of multilateral partners.
Despite the commitment to a renewed US–Philippines alliance, its long-term success will largely depend on how the Marcos administration manoeuvres domestic opposition. Various groups including the Filipino–Chinese business community, former president Rodrigo Duterte, and Marcos’ sister oppose an alignment with the US in the face of China. As a result of this, Philippine Foreign Secretary Enrique Manalo expressed in his most recent remarks in Washington a mix of joy and caution within alliance commemorations. For the US–Philippines alliance to succeed and adapt to the realities of the 21st century, it must become stronger, more resilient and wary of domestic opposition.
Narupat Rattanakit is a Fellow in the Pericles Institute, a think tank based at American University.