The Treaty on the Non-Proliferation of nuclear weapons turns 56 this year, and it is showing its age. Diplomats gathered at UN Headquarters for the treaty’s 11th review conference as the number of nuclear warheads rises for the first time in decades, global military spending hits $2.7 trillion and nuclear testing is again being discussed openly. Mr. Guterres told the General Assembly that the treaty must evolve to survive the era of artificial intelligence and quantum computing. “We need to breathe life into the Treaty once more,” he said. Do Hung Viet of Vietnam, elected conference president, warned that two previous review conferences, in 2015 and 2022, failed to reach consensus. A third failure, he implied, might prove fatal to the treaty’s relevance.

Before proceedings could begin, a diplomatic spat broke out over Iran’s nomination by the Non-Aligned Movement as a vice-president of the General Committee. The United States called the move an “affront to the NPT,” citing Iran’s nuclear advances. Russia accused Washington of politicising the conference from the outset. Iran dismissed the objections as baseless. A fragile compromise was reached: objecting states formally disassociated themselves from the decision rather than force a vote. The conference runs until May 22.