Transnational Parliamentary Governance: A Catalyst for ‘TPNW Universalization

The supporters of the Treaty on the Prohibition of Nuclear Weapons (TPNW) face a twofold challenge: establishing an effective treaty infrastructure (vertical approach) and convincing more states to join (horizontal approach). This paper argues that the horizontal approach should take precedence in the short term, as universalizing the Treaty can maximize the TPNW’s authority, norms, and principles—which can also serve the vertical approach. To achieve TPNW universalization, various discourses and narratives on the Treaty’s utility are needed. In accordance with Article 7 of the TPNW, the paper proposes that transnational parliamentary governance could be a compelling and effective driver for universalizing the Treaty. Transnational parliamentary governance involves numerous regional and global parliamentary bodies that can develop a distinct supportive TPNW narrative with a significant outreach to and impact on the UN member states’ legislative bodies. It focuses on the Inter-Parliamentary Union as the case study, illustrating its potential to foster a parallel TPNW discourse worldwide that aligns with the Treaty’s vertical approach.