How do alliances trade arms? Political alliance networks and global arms transfers.

The arms trade has come to the center stage of the international political economy. Yet only a few quantitative studies have been conducted on the political economy of the arms trade. This paper focuses on the security rents shared by trading partners in determining their arms trade relationship. We argue that the mechanism of reciprocity is better understood from the perspective of an international alliance network. Because the rents are likely to be transferred to other related members in a community, when a state is engaged in an arms deal with another state, it takes into account not only the direct dyadic relationship but also the alliance community to which the other state belongs. Based on this understanding, we employ social network analysis (SNA) to identify the effect of the international alliance community on the arms trade. Our findings suggest that if two states have a tie in a political alliance network, they are also likely to have a tie in the arms sale network. Moreover, we also find that the alliance network is a strong predictor of bilateral arms sales. Being in the same alliance community encourages two states to trade more arms with each other.