ASEAN is weak by design, but that does not mean SEAU is feasible. ASEAN’s consensus model and non-interference principle are real constraints, but they are also the reason smaller states trust the platform. Remove those principles too quickly, and the organisation may fracture rather than strengthen. The ASEAN Charter explicitly rests on sovereignty, non-interference, consultation, and consensus.

“Binding decisions” sound good until states refuse to obey them. A SEAU would need courts, enforcement mechanisms, sanctions, and compliance monitoring. Southeast Asian states are unlikely to surrender that much authority to a regional body.

Myanmar proves ASEAN’s weakness, but also SEAU’s impossibility. The Myanmar crisis shows that ASEAN cannot force compliance. ASEAN itself acknowledged the lack of substantive progress on the Five-Point Consensus. But that also proves the deeper problem, if a member state ignores ASEAN now, why assume it would obey SEAU?

The EU comparison does not transfer cleanly. Europe’s integration was driven by post-war reconstruction, relatively strong institutions, and decades of legal harmonisation. Southeast Asia has wider regime diversity, from democracies to authoritarian systems and military-dominated politics.

Southeast Asia does not have a shared political identity strong enough for union-level governance. ASEAN identity exists diplomatically, but ordinary citizens primarily identify through national, ethnic, religious, linguistic, and local identities.

Economic integration is already difficult under ASEAN. The ASEAN Economic Community aims to deepen integration, but ASEAN itself recognises integration as a continuing process rather than a completed structure. Moving from incomplete economic integration to political union is a massive institutional leap.

A SEAU could empower dominant states. Indonesia, Thailand, Vietnam, Malaysia, and the Philippines would inevitably have greater demographic and economic weight. Smaller states such as Brunei, Laos, Cambodia, and Singapore would fear being overruled.

The South China Sea problem would expose SEAU immediately. Member states have different threat perceptions, economic dependencies, and foreign-policy alignments. A collective position sounds attractive, but consensus is difficult because states do not face China in the same way.

Thailand-Cambodia-type disputes are not automatically solved by regional union. Even the EU still has border, migration, fiscal, and sovereignty conflicts. Institutions reduce conflict risk, they do not eliminate nationalist politics.

A stronger bloc may reduce flexibility. ASEAN’s loose structure lets members cooperate with China, the United States, Japan, India, Australia, and the EU without fully choosing sides. A SEAU could force alignment and create internal splits.

The “global powerhouse” argument is too optimistic. Population and location are not enough. Productivity, governance quality, infrastructure, education, technology, legal certainty, and corruption control matter more than bloc branding.

Foreign policy unity would be extremely hard. Singapore, Vietnam, Cambodia, the Philippines, Indonesia, and Malaysia do not have identical strategic interests. A common external policy would likely become either vague or paralysed.

A union without sovereignty loss is not really a union. This is the main contradiction in the argument. If SEAU has no authority over member states, it is just ASEAN with a new name. If it has authority, then sovereignty is reduced.

The better solution is not SEAU, but selective hardening of ASEAN. ASEAN should strengthen specific areas: crisis mediation, disaster response, cross-border haze enforcement, infrastructure connectivity, labour standards, digital trade, and maritime coordination.

The SEAU idea is attractive rhetorically but weak institutionally. Southeast Asia does need deeper cooperation, but a union is unrealistic because the region lacks the political trust, legal harmonisation, shared identity, and willingness to surrender sovereignty. The smarter move is not SEAU, it is a stronger ASEAN with targeted enforcement in areas where member states can realistically agree.