Delegates recently convened in Kampala, Uganda to lay the groundwork for the International Criminal Court’s eventual prosecution of the crime of aggression. This achievement caps decades of negotiations that began in the post-World War II period. From virtually the beginning of the negotiations, it was argued that an aggression prosecution should not go forward absent some definitive showing that a state had committed a predicate act of aggression. Delegations diverged on which body—the Security Council or the court itself—should be empowered to determine whether a predicate act of aggression had occurred and whether it was necessary for the putative aggressor state(s), the victim state(s), or both, to have consented to the court’s jurisdiction before a prosecution could proceed. The end product was an unimpeachable regime of state consent that completely insulates the nationals of Non-Party States from prosecution and allows States Parties to opt out of the crime entirely. The results achieved in Kampala have subtly eroded the primacy of the Security Council, as states revealed a preference for a consent-based regime and a willingness to extend international criminal jurisdiction to their own nationals and over their own foreign policies. Indeed, the aggression amendments may have actually diminished the efficacy of the Council’s pre-existing referral power and created the potential for greater conflict between the Council and the court. The outcome in Kampala thus presents a microcosm of the continual thinning of state sovereignty and the indelible shift in the balance between power and law in international relations. This Article examines the aggression amendments and the process by which they were adopted, concluding with a discussion of the way in which the negotiations and the final amendments invoked and rebalanced the central themes of power politics, state consent and judicial independence within public international law.