This chapter summarizes the book’s main findings and discusses five major contributions to the study of transitional justice (TJ) as a powerful force to prevent criminal wars in new democracies: (1) the importance of conceptualizing organized crime as a hybrid field of state–criminal networks, where state specialists in violence play a central role; (2) TJ’s power to influence peace and war in the criminal underworld by exposing and sanctioning state specialists in violence; (3) the crucial role of state accountability for the development of peaceful democracies; (4) the importance of dismantling violent counterinsurgent states by means of justice before electoral competition becomes routinized in new democracies; and (5) the dangers that the survival of the counterinsurgent state and its militarized public security practices, and the persistence of criminal wars, pose for the integrity of democratic regimes. The book ends with a reflection on Third Wave democracies. In the mid 1980s, scholars of democratization warned elites and societies to renounce (or at least postpone) demands for accountability for past atrocities to avoid a military backlash that would compromise democratic stability. Accountability Shock draws a different conclusion: Failure to address a repressive past paves the way for a future of democratic instability, large-scale violence, and gross human rights violations.