OSLO – Russia’s invasion of Ukraine has elevated global nuclear tensions to a level not seen since the height of the Cold War. Absent any signs of responsible leadership from Russian President Vladimir Putin, it is incumbent on the leaders of other nuclear-armed countries to take practical and prompt action to de-escalate, counter immediate threats, and agree on common steps toward non-proliferation and eventual disarmament. The war in Ukraine, accompanied by Russia’s nuclear saber-rattling, ha