The CTBT at 25 and Beyond

This year marks a major milestone for the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The multilateral body was founded to support implementation and compliance with the Comprehensive Test Ban Treaty (CTBT), which established a prohibition on all nuclear weapons test explosions anywhere. After a protracted and combative election process against incumbent Lassina Zerbo, Australian candidate Rob Floyd prevailed with a convincing majority; and as of August 1, he has taken over as the CTBTO’s fourth executive secretary.

This change in leadership is expected to breathe new ideas into the management of the organization and could open new avenues for cooperation with countries in the Asia-Pacific region and beyond. At the same time, Floyd and the organization face daunting challenges during a year that also marks the 25th anniversary of the CTBT’s opening for signature in 1996. Although the treaty has successfully halted nuclear testing for a quarter-century, the door to renewed testing and, with it, an accelerated expansion of global nuclear weapons capability remain open because the treaty has not yet formally entered into force.

Despite political and legal uncertainty, the CTBTO and its member states have shown remarkable ingenuity in establishing a successful global monitoring network—the International Monitoring System (IMS)—of unprecedented scale and sophistication. The system relies on superb and still unsurpassed technical capabilities for monitoring and verifying the global nuclear test ban. Nevertheless, serious technical and political challenges to the long-term sustainability of the organization and the monitoring system are slowly emerging. Consequently, although this would be undesirable and politically costly, the international community should consider taking steps to decouple the IMS from the treaty’s fate in order to maintain and expand on the extraordinary technical investments that the monitoring system represents.