Free Riding, Network Effects, and Burden Sharing in Defense Cooperation Networks

Abstract How do states distribute the burdens of collective defense? This paper develops a network theory burden sharing. We focus on bilateral defense cooperation agreements (DCAs), which promote in variety defense, military, and security issue areas. Using computational model, we show that DCA partners’ spending depends structure their agreements. In terms, DCAs increase by committing to activities allowing partners reciprocally punish free riding. However, as state's local partnerships grows more densely connected, with many transitive “friend friend” relations, have countervailing effect reducing spending. The deeply integrated are networks, less they spend defense. distinguish two potential mechanisms behind this effect—one based efficiency improvements, other An empirical analysis using multilevel inferential models points than Defense networks reduce spending, so countries produce efficiently.