Rethinking SEATO: A new maritime pact for ASEAN?

Focus Malaysia

09-06-2025

AS geopolitical tensions escalate in the Indo-Pacific, Southeast Asian nations find themselves increasingly vulnerable to the turbulence sweeping the region.
China's growing assertiveness in the South China Sea, the rising strategic competition between the United States (US) and China, and the proliferation of non-traditional maritime threats such as piracy and illegal fishing have converged to create a volatile security environment.
Against this backdrop, a provocative question has resurfaced:
Should the Association of Southeast Asian Nations (ASEAN) revive the Southeast Asia Treaty Organisation (SEATO) as a mechanism to bolster regional maritime security?
SEATO, founded in 1954 and dissolved in 1977, was originally designed as a Cold War-era collective defence pact aimed at containing communism. Its legacy is, at best, mixed.
With only two Southeast Asian members i.e., Thailand and the Philippines and heavily dominated by external powers like the US, United Kingdom, and France, SEATO was often criticised for its lack of cohesion and legitimacy within the region.
Its failure to evolve into a true collective security mechanism contributed to its irrelevance and eventual dissolution.
Yet in 2025, the strategic landscape has changed dramatically. Today, the Indo-Pacific is the epicentre of global power politics, and ASEAN's role has never been more crucial.
The organisation stands at a crossroads: continue with its consensus-based, non-aligned approach, or adapt to a more assertive and structured security framework in response to rising threats.
The idea of reviving SEATO or at least, reimagining it should be explored seriously, but with critical adjustments grounded in current realities.
Maritime security: ASEAN's Achilles heel
Southeast Asia's maritime domain is a focal point for multiple overlapping claims, economic interests, and military ambitions. The South China Sea alone sees one-third of global shipping pass through its waters.
Yet, maritime security remains ASEAN's Achilles heel. Despite initiatives like the ASEAN Maritime Forum and joint patrols in the Sulu and Celebes Seas, the region lacks a comprehensive, cohesive maritime defence structure.
In the face of China's continued island-building, coercion of fishermen, and incursions into Exclusive Economic Zones (EEZs), ASEAN's diplomatic toolbox seems increasingly inadequate.
Reviving SEATO or creating a SEATO 2.0 could offer a more robust framework to pool resources, share intelligence, and establish clear deterrents.
Unlike its Cold War predecessor, a modern version would need to be rooted in ASEAN leadership, rather than being externally driven. This could transform it from a symbol of neo-colonial entanglement into a proactive regional safeguard.
A reimagined SEATO: ASEAN-led and inclusive
Any modern iteration of SEATO must be fundamentally different in design and intent.
First and foremost, it should be ASEAN-led, preserving the centrality of the organisation. External partners such as the US, Japan, Australia, and India could serve as dialogue or strategic partners, but not dominant actors.
This would maintain ASEAN's long-held position of neutrality while enabling it to take a more assertive role in shaping regional security.
The objectives of a new SEATO would also need to evolve. Rather than being a purely anti-China alliance, it should focus on enhancing maritime domain awareness, building naval interoperability, strengthening coast guard cooperation, and securing sea lines of communication.
These goals are inherently defensive and could gain broader support among ASEAN's diverse members, many of whom are wary of becoming pawns in great power rivalries.
This reimagined SEATO could also be integrated into the broader Indo-Pacific security architecture. Coordination with initiatives like the Quadrilateral Security Dialogue (Quad), the Indo-Pacific Partnership for Maritime Domain Awareness (IPMDA), and the Regional Cooperation Agreement on Combating Piracy and Armed Robbery against Ships in Asia (ReCAAP) would create a multi-layered and resilient defence posture.
Challenges and caveats
However, reviving or rebranding SEATO is far from a silver bullet. ASEAN's core principles are non-interference, consensus-based decision-making, and respect for sovereignty, often inhibit swift or unified responses to crises.
Member states have varying security priorities and relationships with major powers. For instance, Cambodia and Laos maintain close ties with China, while the Philippines and Vietnam are more confrontational. This divergence makes the formation of a formal security pact challenging.
Moreover, introducing a SEATO-like structure risks undermining ASEAN unity if not managed carefully. It could exacerbate intra-regional tensions and provoke backlash from China, which may interpret it as an encirclement strategy. Balancing deterrence and diplomacy will be crucial.
The path forward: Pragmatic regionalism
Rather than a wholesale revival of SEATO, ASEAN should consider a flexible, modular approach.
A 'SEATO-lite' framework beginning with joint maritime exercises, intelligence sharing, and capacity-building—could evolve organically based on the needs and consensus of member states.
This incremental strategy would avoid the political costs of formalising a defence pact while still enhancing maritime cooperation.
Additionally, ASEAN should push for institutional reforms that allow for 'ASEAN Minus X' models where willing members move forward on specific security initiatives without requiring unanimity.
This would preserve the group's cohesion while allowing progress on urgent maritime issues.
Conclusion
The notion of reviving SEATO as a means to strengthen maritime security in Southeast Asia is both provocative and timely.
While the historical baggage of the original SEATO looms large, the current strategic environment demands fresh thinking. A reinvented, ASEAN-led security framework whether called SEATO or something new could be a pivotal step in safeguarding the region's maritime future.
ASEAN must not allow itself to be paralysed by its past or by external pressures. The Indo-Pacific is evolving rapidly, and so too must Southeast Asia's security architecture.
Whether through a revived SEATO or an entirely new model, one thing is clear: the time for passive neutrality is over. ‒ June 9, 2025
R Paneir Selvam is the principal consultant of Arunachala Research & Consultancy Sdn Bhd, a think tank specialising in strategic national and geopolitical matters.
The views expressed are solely of the author and do not necessarily reflect those of Focus Malaysia.
Main image: AP Photo/Sakchai Lalit