For years, the South China Sea has been seen primarily as a flashpoint in the intensifying geopolitical rivalry between China and the United States. But a new, subtle security network is taking shape across the region, built not around formal alliances but around access deals, missile sales, coast guard drills, intelligence-sharing talks and defense consultations.
On June 1, the Philippines and Vietnam upgraded ties to an enhanced strategic partnership and signed a memorandum on defense cooperation, committing to high-level exchanges, strategic dialogue, information sharing and joint activities at sea. The partnership builds on earlier coast guard arrangements, including a hotline and mechanisms to prevent incidents.
Late last month, Indian officials said New Delhi had signed a $629 million deal to supply Vietnam with the BrahMos supersonic cruise missile system. Vietnam is the second Southeast Asian buyer publicly confirmed by India, after the Philippines. The missiles are jointly developed by India and Russia.
Meanwhile, Japan's security relationship with the Philippines has grown concrete. A Reciprocal Access Agreement entered into force last September, expanding troop deployment, while this month they began talks over a new deal to share classified defense information. In February, Australia and Indonesia signed the Jakarta Treaty, a common security pact committing to regular top-level consultations.
None of these agreements creates a NATO-style alliance. Together, however, they show how middle powers are trying to make unilateral pressure at sea harder and costlier. All these countries share concerns about China and an interest in upholding the rule of law at sea, according to Hunter Marston, director of the Southeast Asia Program at the Lowy Institute.
The Philippines has moved the fastest. Since President Ferdinand Marcos Jr. entered office in 2022, Manila has become more willing to publicize Chinese pressure and widen defense cooperation beyond its main ally, the United States. Marcos Jr. said the upgrade with Vietnam reaffirms Vietnam's unique position as the sole strategic partner of the Philippines in Southeast Asia.
India's role is different. New Delhi is not a South China Sea claimant, but the BrahMos deal gives its Act East policy a harder edge. For Hanoi, the missile system strengthens coastal defense. For New Delhi, it shows its Indo-Pacific policy is no longer only about diplomacy and trade.
Despite Vietnam's public disputes with China, Hanoi remains cautious, seeking to preserve strategic autonomy and avoid formal alignment, said Kei Koga of Nanyang Technological University. Indonesia is more cautious still, not describing itself as being in a territorial dispute with Beijing.
Tokyo was once far more cautious about security cooperation, given constitutional limits. That is now changing. The Japan-Philippines Reciprocal Access Agreement was the first of its kind with a Southeast Asian country. Australia's Jakarta Treaty with Indonesia points in the same direction.
China remains the largest trading partner of most Southeast Asian countries, making regional players wary of antagonizing Beijing. These expanding defense partnerships are still loose, flexible and uneven, with no integrated command structure or formal collective-defense commitment, said Koga. They are primarily about strengthening each state's own capabilities.
Source: www.dw.com