| The phenomenon of third party intervention in domestic political disputes has posed a significant dilemma for international relations scholars and practitioners for several decades. Specifically, why do third parties decide to intervene in some intrastate disputes, but decide not to intervene in other intrastate disputes? The question of why potential third parties choose to intervene in some cases but not in other cases has been widely discussed among international relations scholars and practitioners for several decades, but very few systematic analyses of the question have been conducted by international relations scholars. In this study, I intend to deal with some of the deficiencies in the international relations literature on third party interventions in intrastate disputes.; After describing the phenomenon of third party interventions in intrastate disputes in the 20th century, I develop hypotheses regarding the occurrence of state interventions and intergovernmental organization (IGO) interventions in domestic political disputes. Hypotheses are tested using originally-collected data on some 3,102 cases of third party interventions (including 1,669 state/coalition of states interventions, 573 United Nations interventions, and 860 regional IGO interventions) in some 400 intrastate disputes during the 20th century. Using Logit regression analysis, I find that a combination of strategic (international) linkages and nonstrategic (transnational) linkages had significant effects on the occurrence of state interventions during the 20th century. I also find that a combination of security, political, humanitarian, and normative considerations had significant effects on the occurrence of UN and regional IGO interventions during the post-World War II period. |
