The theoretical benefits of shared development costs and interoperability in armaments collaborations have led to an increase in cooperative projects, and the policy’s popularity is only likely to grow. Nevertheless, most states fail to achieve their desired levels of collaboration. The question must therefore be raised as to what factors favour partnerships’ success.
We argue that realist dynamics play a more significant role than hitherto appreciated. International armaments collaboration is a fundamentally difficult process. Major projects cost significant sums and often require decades to complete. Multiple stakeholders, ranging from military headquarters to corporate managers, may calculate that cooperation no longer serves their interests. Governments therefore need powerful incentives to overcome domestic opposition for collaboration to succeed. Realist interests – notably, the sense of collectively balancing against threats – provide governments with the requisite motivation to overcome domestic discontent. States within alliances stand to benefit more from collaboration because they alone profit from collaboration’s interoperability advantages. Alliances, furthermore, offer assurances in terms of supply security – sometimes through formal arrangements and at others through states’ common interest in not jeopardising the alliance – that mitigate this risk. Realist concerns, as expressed in formal alliances, thus incentivise governments to steer projects through to completion.