From 2006 to 2014, Thailand cycled through ten prime ministers, five interim and permanent constitutions, and a mix of "free," "partly free," and "not free" political systems. To many Thailand observers, the instability during these first years of the new millennium were a continuation of a historical trend; indeed, Thailand has hosted more attempted coups in the past century than any other country. However, while regimes have been subject to extreme instability, regime types have been more stable. Since 1932, Thailand has experienced sustained periods of both authoritarian and democratic rule. The pendular swings between regime types from 2006 to 2014 mark a departure from this trend. This essay posits that Thailand's dramatic oscillations can be understood as a consequence of playing an "impossible game": a structure of political competition whereby two starkly divided political coalitions are equally capable of vetoing each other's successes. Guillermo O'Donnell devised this game theoretic model to describe the political instability characterizing Argentina from 1955 to 1966. By analyzing political competition in Thailand against the essential features of O'Donnell's model, I derive four interdependent hypotheses to explain the inability of Thai political actors to stabilize either authoritarian or democratic regimes. Finally, as with any model, this game theoretic approach suggests expected consequences. I offer implications for Thailand's political development as it emerges from these years of fraught and futile competition.