The plight of David Hicks, an Australian imprisoned in Guantánamo Bay, raised widespread concern among the Australian community. One question frequently asked was why the Australian Government would not do more to secure his release. The lack of action by Australia during Hicks’s five years of incarceration led his lawyers to consider what other avenues of protection may be available. The discovery and recognition of Hicks’s entitlement to British nationality in addition to his Australian nationality opened up the possibility of Hicks being treated in a comparable manner to other British nationals held in Guantánamo Bay — namely, his release from that prison and repatriation to the United Kingdom. Hicks’s acquisition of dual nationality raised many issues related to Australia and the United Kingdom taking action on his behalf against the United States through their right of diplomatic protection. This article explores why the nationality of David Hicks was significant in efforts to protect his rights and how he was reliant on the actions of Australia and the United Kingdom to exercise their right of diplomatic protection. Despite increasing recognition that the right of diplomatic protection is an important tool in the promotion and protection of human rights, the situation of David Hicks demonstrates that diplomatic protection remains bound in a state-centric construct. As a result, an important means of vindicating individuals’ human rights was denied.