This thesis examines the relationship between third party state intervention in civil conflicts and the likelihood that an intervening state will become the target of terrorist attacks by other combatants in that conflict. In doing so, this thesis builds off of the root causes theory of terrorism to examine how different types of intervention might exacerbate or alleviate conditions that foster the emergence of terrorist organizations in civil conflict areas, or affect public support and recruitment opportunities for terrorist organizations once they emerge. By utilizing principal-agent theory this thesis examines the potential dangers that states may face when enlisting governments or insurgent organizations as agents within an internationalized civil conflict. This thesis considers the effects of direct military support for a belligerent in a civil conflict versus indirect material or logistical support to determine whether different tactics deployed during an intervention affect the likelihood of terrorist reprisals in different ways. Similarly, this thesis examines interventions on behalf of governments and on behalf of insurgent organizations separately to determine if the type of actor that an intervening state supports has differing effects on the incidence of international terrorism against the intervening state.