Despite a wide recognition that external relationships are a significant force in shaping the pattern of Australian economic and political history, available theories for analysing the interplay of external and internal processes -- political sociology, dependency and world systems theory -- do not provide a reliable basis for coming to tenns with this aspect of Australia's historical experience in a contemporary setting. The world-historical perspective, as developed in an Australian context by McMichael, does addresses this problem usefully, but it is of limited contemporary utility since it largely focuses on the colonial period of the first half of the nineteenth century when Australia's economic structure and political institutions were relatively undeveloped. Two major areas of theoretical debate are addresed in chapters two and three. Chapter Two critically re-evaluates the utility of political sociology for a world-historical approach by analysing debates about nation-state territoriality. In Chapter Three the discussion considers dependency and world system perspectives, as well as couurent debates within international relations through a critical a~sessment of their approach to the historical development of the nation-state system. The thesis then proposes a re-evaluation of the applicability of the notion of hegemony to the study of relationships between nation-states, and a conception of a regime-governed international order as an alternative to the current approaches. Within this conceptual framework, the thesis focuses on a case study of the establishment, consolidation and decline of United States hegemony, and the concomitant decline of British power, in the Asia-Pacific region, and Australia's active engagement with this historical process. The ways in which this external program of United States regime-building impinged upon Australian domestic politics and established an external source of state legitimacy for both Labor and conservative governments is analysed in chapters Five and Six. These chapters also discuss the effects on the economic and political transformation of Australia from the l930s to the 1950s and continuing problems which follow the aftermath of the defeat of the 'Western alliance' in Vietnam and the onset of the global recession. The concluding chapter consolidates the linkage between the empirical and theoretical content of the thesis in order to propose a conceptual approach to the study the relationships between nation-states and the international order and to apply this approach to a consideration of the future prospects for Australia.