Until now, the alliance has chosen to ignore calls for change and has eschewed public debate. Nato clings to the outmoded notion that the 200 or so gravity bombs in five European countries are a necessary deterrent (against Russia, which has an estimated 4,000 short-range nuclear weapons). The status quo has prevailed with the US saying it is waiting for an allied request to remove the B61 bombs from Germany, the Netherlands, Belgium, Italy and Turkey. But this has never happened, partly because of resistance from some former Soviet bloc states within Nato. They have been virulently opposed to the removal of the weapons which they perceive as a guarantee of a US presence in Europe against Russian aggression.
And so, since the cold war, these bombs which serve no military purpose, which arguably violate a global disarmament treaty (the nuclear non-proliferation treaty) and which pose a potential security threat in the heart of Europe, have lingered. They were secretly deployed under Nato's "nuclear sharing" policy at a time when the major security threat facing the west was the Soviet Union, not terrorists.
But suddenly the tide is turning. In recent weeks it has become clear that the status quo is no longer an option, as the host states themselves have stepped up a co-ordinated campaign – presumably with a nod and a wink from Washington. Four senior Belgian politicians on Friday became the latest "quartet" from a country hosting B61s to call for their removal.
The pressure began mounting last autumn, when the new coalition German government began the assault on the Nato nuclear weapons in Europe, and called for the removal of the 20 bombs on German territory. Then, four Dutch statesmen called on Nato to take away theirs. Now Belgium has joined the chorus, after the debate took a new turn last week when a former Nato head, Lord Robertson, attacked Germany's stance. According to a report by Agence France-Presse, which quoted the Belgian prime minister's office, Belgium, Germany, Luxembourg, the Netherlands and Norway plan a joint call in the coming weeks to urge the weapons' removal from all of Europe.
The predominant argument for seeking their withdrawal is that they no longer serve any credible deterrent role. In Turkey for example, which has up to 90 gravity bombs – that require specially trained forces to load them onto US planes – the B61s would take months to deploy. Russia is perfectly aware that it is 33 minutes away from an intercontinental ballistic missile coming over the horizon from America, if it should resort to firing one of its own short-range nuclear weapons. Military experts agree that the scenario of a Russian deliberate nuclear strike is far in the past and that any future threat is more likely to feature 21st-century means such as a cyber attack.
The removal of these cold war relics would be a real disarmament step, at a critical time when the nuclear weapons states, and Nato itself, expect to come under diplomatic attack on their disarmament record at a global conference in May. What is more, if carried out sensitively, the withdrawal should actually provide an opportunity to enhance Nato cohesion rather than destroy it.
Polish foreign minister Radek Sikorski and his Swedish counterpart Carl Bildt have come out in favour of their removal. Given Poland's experience of Soviet occupation and military dictatorship, Sikorski's co-authorship of an article in the New York Times was striking. It is to be hoped that policymakers in the Czech Republic and Baltic states can break out of the cold war mould that still defines so much of Nato thinking. Russia may be a neighbourhood bully, but it is weak: in the long term its salvation lies through cooperative, not antagonistic, relations with the west.
Thanks to the Strategic Concept Review now under way in Nato capitals, with the first phase shepherded by Madeleine Albright and her Group of Experts, the alliance has the first chance in a decade to place itself on the right side of history. There is now a global consensus "to create conditions for a world without nuclear weapons", in the words of UN security council resolution 1887. The major capitals of the world are debating how to reduce their reliance on nuclear weapons and how to express this through nuclear doctrines. Nato is finally having to get to grips with the issue of the B61s in Europe, at a seminar in Washington this week, and next weekend in Rome.
So it really is decision time for Nato. Its policymakers and military establishment must address the deployment of 200 US Air Force nuclear bombs in five European countries. They should engage creatively with their central European colleagues and Turkey on security needs and look to the future, not the past.