Pro-government international military intervention during genocide and politicide

Why do states intervene militarily to support regimes that are committing genocide or politicide? Previous literature examines why states intervene to stop such atrocities, but overlooks why some states support murderous regimes. I argue that states support lethal regimes when such support is militarily and strategically beneficial. In particular, I posit that third-parties are likely to support their allies in time of civil war, despite murderous policies. Statistical analysis of all genocides and politicides between 1955 and 2005 supports this argument. Importantly, I also find that third-parties are no less likely to support lethal regimes in the post-Cold War era. These findings question whether normative change in the international environment is influencing state decision-making on important military calculations.