Changing Structure of the Arms Trade: a Social Network Analysis

The global arms trade should be understood not as a market but as a network, one that shares some important properties with networked forms of organization studied by sociologists. I make this argument and then employ quantitative methods developed for social network analysis in an effort to describe the evolving structure of the arms trade network since the end of World War II. That structure has changed significantly over the past fifty years. It became less dense in the early years of the cold war as newly independent states joined the society of states, but had yet to develop many arms-transfer ties. But from the early 1970s, the network got denser as armstransfer relations developed among a roughly constant number of actors. At the same time, the supplier structure of the arms trade has become progressively less centralized, even though the United States remains the most central arms supplier. This decentralization is evident from the patterns of arms-transfer relationships in the network, not from aggregate amounts of weapons transferred by the United States and other suppliers, which paint a quite different picture (one of greater U.S. predominance). Mapping the positions of arms suppliers in two-dimensional space sheds some more light on structural changes within the network. Aside from Russia, which maintains several arms-transfer relationships established during the cold war, the leading arms suppliers share an expanding set of common clients. Many analysts of the arms trade have commented on the increasing competition among arms suppliers in the post-cold war era, and the evolving structure of the arms trade seems conducive to further marketization.