Few issues are more important to scholars of Europe’s emergence as a security actor than understanding European armaments collaboration’s evolving institutional context. However, European states’ decisions as to what forms of organization to promote defy simple categorizations. Indeed, European states have alternatively, and sometimes simultaneously, favored such variegated arrangements as: intergovernmental collaboration under the EU Council’s aegis, supranational regulation by the European Commission, cooperation through NATO, and the creation of specialized international organizations unaffiliated with either the EU or NATO. This paper explores why European states have pursued armaments through such a variety of international organizations. To this end, it comparatively tests hypotheses derived from realism, liberalism and constructivism. To preview my conclusions, liberal incentives to preserve high technology industries and realist impulses to collectively improve military effectiveness drove European decisions at distinct periods of time as to which aspects of armaments cooperation to embed in what form of international organization.
