New confidence-building measures can reduce tensions around subcritical tests

With rising tensions between the United States on one side, and China and Russia on the other, the three countries have grown mutually accusatory about some testing activities they conduct to maintain and modernize their nuclear arsenals, with allegations made by the United States focusing on very low-yield fission experiments. In a world where trust in the nonproliferation regime is weakening and most bilateral arms control measures have been suspended, many experts fear that recriminations over very low-yield tests could spark a new escalation spiral to full-scale nuclear tests. Transparency measures could diffuse the suspicions around these tests and strengthen the Comprehensive Nuclear Test Ban Treaty, which is largely being complied with but still not legally in force.