the concept of a region suggests that the societies incorporated within it, while undoubtedly differing in certain significant ways, share some fundamental characteristics that provide them a regional quality. Issues that have affected one society have likewise influenced other societies; there have been shared historical, social, and political experiences. Moreover, increasing economic integration (internal trade and investment flows, convergence of economic systems) supports the suggestion that East and Southeast Asia is a region. Regionalisation of politics, through institutions such as the Association of Southeast Asian Nations (ASEAN), is also premised on an increasing convergence of political interests between the nations of East and Southeast Asia. Finally, the case for characterising East and Southeast Asia as a region is built on its importance to Australia. From the Australian perspective, East and Southeast Asia is ‘its region’. Australia's economic, political and strategic interests are closely and increasingly linked to developments in the region, and Australia has increasingly adopted a regional foreign policy response to developments in East and Southeast Asia (see Chapter 12).

Establishing East and Southeast Asia as a region is thus a necessary, though problematic, starting point for analysis. Without the construct of a region, some other unit of analysis would be required as our primary focus; this might be the nation or sub-national communities. However, these, like the idea of a region, are constructs based on criteria that establish them as objects of observation and analysis.