Is “Global Zero” constructive?

On 5 April 2009, US President Barack Obama declared in Prague that his presidency would affirm "America's commitment to seek the peace and security of a world without nuclear weapons”. Obama’s speech rekindled the vision of a nuclear-free world and enlivened the discussion on the steps needed to achieve it. Yet the event should really have been of limited news value. After all, every US  president, except Obama’s predecessor George W. Bush, has paid lip service to the dawn of a nuclear-free world. And the United States, just like the other nuclear powers, Russia, China, France and United Kingdom, undertook back in 1968 under the terms of the Nuclear Non-Proliferation Treaty “to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control.”

In 1985, still in the context of the Cold War, the nuclear-weapon states had a combined arsenal of more than 60,000 nuclear weapons—an overkill capacity to destroy the world many times over. Around 98 per cent of all nuclear weapons were in the hands of the United States and the Soviet Union. With the collapse of the Soviet Union and the end of the East-West antagonism, the nuclear weapons count underwent a sharp decline: In 2005, there were still 27,000; in 2013 around 17,270 (figures from "World Nuclear Forces", “SIPRI Yearbook 2013: Armaments, Disarmament, and International Security” Stockholm International Peace Research Institute, Oxford, p. 283f). Of these, Russia holds around 8,500, the United States 7,700, France 300, China 250 and the United Kingdom 225 warheads. These five pre-treaty nuclear powers have since been joined by India and Pakistan, each with approximately 90 to 120 and by Israel with around 80 nuclear warheads.

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