The 2009 adoption of the EU directive on intra‐Community transfers of defence equipment (‘ICT directive’) (2009/43/EC) aims to harmonize defence transfer licencing in the EU. The directive is part of a ‘defence package’ – along with a directive on defence procurement (2009/81/EC) – that is geared to liberalizing and regulating the European Defence Equipment Market (EDEM). A major theoretical question is why the EU Member States would agree to the ICT directive when it did not ultimately make much difference to the functioning of the EDEM. A number of competing theories exist that help explain why the 2009 ‘defence package’ was adopted. In the hope of engaging with this theoretical debate, and expanding our empirical understanding of the ICT directive, this article contends that insights from judicial politics, economic patriotism and liberal intergovernmentalism are best placed to explain why the EU Member States eventually adopted the directive.