International Military Intervention (1946-2005)

Updates International Military Intervention (IMI), 1946-1988. This newer study documents 447 intervention events from 1989 to 2005. To ensure consistency across the full 1946-2005 time span, the original coding procedures were followed. The data collection thus "documents all cases of military intervention across international boundaries by regular armed forces of independent states" in the international system). "Military interventions are defined operationally in this collection as the movement of regular troops or forces of one country inside another, in the context of some political issue or dispute". As with the original IMI (OIMI) collection, the 1989-2005 dataset includes information on actor and target states, as well as starting and ending dates. It also includes a categorical variable describing the direction of the intervention, i.e., whether it was launched in support of the target government, in opposition to the target government, or against some third party actor within the target state's borders. The intensity of the military intervention is captured in ordinal variables that document the scale of the actor's involvement, "ranging from minor engagement such as evacuation, to patrols, act of intimidation, and actual firing, shelling or bombing". Casualties that are a direct result of the military intervention are coded as well. A novel aspect of IMI is the inclusion of a series of variables designed to ascertain the motivations or issues that prompted the actor to intervene, including to take sides in a domestic dispute in the target state, to affect target state policy, to protect a socio-ethnic or minority group, to attack rebels in sanctuaries in the target state, to protect economic or resource interests, to intervene for strategic purposes, to lend humanitarian aid, to acquire territory or to dispute its ownership, and to protect its own military/diplomatic interests. The variable, civilian casualties, which complements IMI's information on the casualties suffered by actor and target military personnel has been added. OIMI variables on colonial history, previous intervention, alliance partners, alignment of the target, power size of the intervener, and power size of the target have been deleted.