It’ll leak.
Olga Oliker et al. 23, Adjunct Professor, Johns Hopkins School of Advanced International Studies; Franziska Stärk, Researcher, Institute for Peace Research & Security Policy, University of Hamburg; Dmitry Stefanovich, Research Fellow, Center for International Security, Primakov National Research Institute of World Economy & International Relations; Maren Vieluf, Policy Consultant, International Campaign to Abolish Nuclear Weapons, "Truth or Dare: Transparency, Ambiguity, and Prospects for New International Commitments in The Nuclear Realm," Deep Cuts, No. 15, January 2023, pg. 5.
Moreover, information on nuclear postures may leak (perhaps intentionally to help strengthen deterrence) or be stolen. Intelligence collectors gather data about other states’ arsenals using a variety of tools, many of which are growing ever-more capable as surveillance technology improves. If this information is rarely if ever shared with the public, civil society and academic researchers combine what governments provide with what they and others observe, including data gathered from leaks, open-source intelligence, and other materials to estimate arsenals and strategies.11 Indeed, the capacity for open source estimations has become even more robust as monitoring and verification technologies have become more and more accessible. The difficulty of keeping at least some information confidential can encourage states to be more transparent themselves, for instance to reduce the bureaucratic costs of classification and to better control the message when information makes it out regardless.12