This thesis explores the motivations behind Bolivias refusal to sell natural gas to neighboring country Chile. It focuses on the backlash surrounding the 2003 Gas Wars and the non-cooperation that followed. Specifically, it analyzes two casesin the 2000s and 1950swhen Bolivia successfully cooperated with Chile in the petroleum sector. While many scholars argue that rivalry has motivated Bolivias decision to avoid cooperating with Chile, this thesis challenges that position. This thesis hypothesizes that three factors, when all present, contribute to Bolivias decision not to cooperate with Chile in the natural gas sector. The first factor that influences this decision is disillusionment with the governing administrations economic policy. This disillusionment leads to both the administration losing credibility and the populace approaching its policy with distrust. If this factor is present, it creates the opportunity for oppositional political elites to leverage the other two factors, resource nationalism and rivalry with ChileBolivias most politically charged and compelling narrativesto fully impede cooperation. This thesis tests this theory on both case studies.