Since the invention of sound-transcription devices in the early nineteenth century, philosophers, linguists, inventors, audiences, and others have debated whether it is the meaningful act of speech or the material sound of the voice itself which defines the speaking subject in the person's absence. Though this question has a long philosophical history, it took on a directly political and practical turn in the United States on 12 November 2002. On that day, Al Jazeera broadcast a tape purported to contain the voice of Osama bin Laden. Programs for political action hinged on a classic philosophical question: How could anyone know for certain if the voice on the tape belonged to bin Laden? This paper offers a political and philosophical analysis of debates surrounding the voice on the tape. It considers the circulation of the tape, the press coverage it received, the techniques of verification used (and not used) to determine the tape's authenticity, and the relationship between bin Laden's voice and his face in American political discourse. The debates around the tape demonstrated that the relationship between the voice and a speaking subject is not simply a matter for epistemology and ontology, but also a crucial matter of power. In order for a bin Laden tape to have its “effects” in politics, action, and debate, it need not be real or validated; it must simply be the subject of belief.