The two core values of international political philosophy are state sovereignty and human rights. Traditionally, of course, the former has dominated: we have hoped that each state will conscientiously protect its constituents' rights, but we have been reluctant to intervene in a country's internal affairs even when it fails spectacularly in this task. Recently, however, our priorities have shifted. We now take human rights more seriously and are correspondingly less deferential to state sovereignty, so a central question of contemporary international ethics is how to adjudicate the tension between state sovereignty and human rights. In this article I argue that, if we take human rights as seriously as we should, then even a legitimate state has no principled objection to outsiders' intervening in its internal affairs if this interference will prevent just a single human rights violation. I defend this stark view by, among other things, showing that it (surprisingly) leaves adequate room for state sovereignty.