The mutual exclusiveness of two types of political integration, i. e., regional and national integration, has been widely accepted: regional integration can take place among those countries which have already completed national integration, but it cannot take place among those which are yet to be integrated nationally. This article challenges this assumption of political integration by discussing a counter-example we are witnessing now.
International relations of insular Southeast Asia have been characterized by a proneness to regional conflicts. The decolonization plan for British territories in the region gave rise to the Philippine claim to Sabah, then a British colony, and Indonesia's anti-neocolonialism campaign. The eventual formation of Malaysia in 1963 caused serious turmoil, which lasted until the downfall of Sukarno. The Sabah problem endangered the new-born ASEAN in the late 1960s, and has from time to time made intra-ASEAN cooperation awkward. Moreover, Muslim separatism and insurgency in the southern Philippines adds another complication to a region where two other countries are Islamic.
Under the surface of such turbulances, however, a joint recognition of the necessity of regional integration has been evolving among the leaders of the countries in the region. In order to integrate their own country individually they must, as they have realized, seek regional integration simultaneously. Consecutive regional conflicts provided the pressure for the leaders to mutually learn that conflictual international relations hamper their individual national integration policies. The framework of ASEAN provided the opportunity for these leaders to transform actual relationships from mutually distrustful to mutually cooperative ones. National integration may not satisfy all the people in these countries; again, regional integration may not satisfy all the peoples in the region. However, the government leaders of these countries share the basic premise that both regional and national integrations are vital, and hence to be pursued simultaneously.
Although the coexistence of these two types of political integration is by no means probable, the ASEAN governments have shown it is at least possible. To change the possibility into an actuality, both governments and peoples in insular Southeast Asia have lost valuable human resources during both regional and local conflicts. Will they have to keep paying such cost in order to pursue political integration?

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