What factors drive the international politics of tertiary states? Constructivists, such as Alice Ba and Aarie Glas, have argued that conflict occurs within the confines permitted by cultures of diplomacy, which are mutually constituted between states. Such analyses eschew structural factors. Structural realists, meanwhile, leave little room in their analyses for the agency of tertiary states to decide their own foreign policies. Following in the footsteps of other scholars of Southeast Asian international relations, this paper will argue that the choices of Southeast Asian states are limited to them by the hierarchical arrangement of the international system, as expressed via alignment choices. One specific manifestation of politics under these constraints is the phenomenon of indirect balancing, wherein states that are otherwise constrained from balancing a hegemonic actor compensate by balancing against their bandwagoning neighbors. Looking at these emerging rifts between states helps us answer the question why conflict continues to occur between Southeast Asian states, despite the presumed dampening effects of international institutions? Conflict has continued to arise among ASEAN members and has even occurred among states with mutual alignment postures- a fact which helps to explain the counterintuitive evidence for increased conflict even as bandwagoning increases in the region. Evidence for this phenomenon of indirect balancing comes from textual analyses of ASEAN documents for evidence of hegemonic intrusion, data on military interstate disputes, and case studies from contentious political moments in the region’s recent history. Understanding this under-studied manifestation of tertiary state power politics can help show how great powers should constructively engage with tertiary powers- a lesson which is especially pertinent in light of a rising China and a United States scrambling to respond to the challenge.