Is the future of Nato under threat?

Article 5 states that “an armed attack against one or more of them in Europe or North America shall be considered an attack against them all… if such an armed attack occurs, each of them [will take] such action as it deems necessary, including the use of armed force” – the principle of collective defence. So far, Article 5 has been invoked once – in response to the US 9/11 attacks.

Have Nato’s purposes and strategy always been clear and agreed?

James Sheehan: The best summary of Nato’s original purpose was the comment attributed to its first secretary general, Lord Ismay, suggesting that the alliance existed to “keep the Russians out, the Americans in, and the Germans down”. For 40 years it succeeded in those three objectives: the United States remained committed to European security, the Soviet Union did not expand into western Europe, and West Germany, though economically powerful and rearmed, did not become a threat to its neighbours.

But despite its long-term success, Nato faced a series of crises, some of them very serious: the postwar division of Berlin, the question of German nuclear weapons, the defection of France from Nato’s military command in 1966, the stationing of medium-range missiles, and many more. At the core of these problems was the fact that the United States was ideologically close but geographically distant from Europe (the opposite was true of the Soviet Union), which meant that Washington and its European allies often saw the world differently. In the end, the alliance survived these crises because there seemed no clear alternative – no one was prepared to accept the risks of a world without Nato.

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Helen Parr: Nato has often been described as an unhappy marriage that not just endured but succeeded. During the Cold War its members were in almost constant disagreement. From its inception Nato was a military pact, committed to defend against attack, and a diplomatic alliance, pledged to deepen institutional and economic collaboration. Three issues repeatedly proved contentious: the balance between nuclear and conventional forces, choices between deterrence and diplomacy or détente, and differences in the relative influence and contributions of the United States and Europe.

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Have Nato members questioned the United States’ commitment to European security in the past?

HP: The Berlin and Cuban crises in the early 1960s raised the chilling prospect of global nuclear war. The Europeans worried that either Nato might not allow a long enough cooling-off period during a crisis before turning to a nuclear response, or the Americans could stand aside and allow Europe to be destroyed. These fears encouraged the maintenance of British and French nuclear forces, and ignited perennial anxieties about the potential consequences of German access to nuclear weaponry.

Because of these concerns, the US and Europe attempted to formulate a more distinctly European grouping within Nato. The West Germans worried that, in any war below the nuclear threshold, German lives and territory would be sacrificed. At the same time, they wanted to keep open the possibility of German reunification, and the Cold War hardened the divisions they hoped to eventually heal. The British guarded against the loss of their nuclear independence in a European grouping; the UK was afraid that France might become the only nuclear power in Europe, and also did not want a German finger on the nuclear trigger. Nor did France, which also feared American dominance would submerge a European identity, and that Britain’s nuclear relationship with America would condemn France to a subordinate status.

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In 1966, French president de Gaulle withdrew France from Nato’s integrated military command structures. The Americans responded by seeking not to push France out of the diplomatic protection of the alliance, but to work around France. Nato established the Nuclear Planning Group to give the Europeans more say, formally adopted the doctrine of ‘flexible response’ to plan for conventional reaction rather than all-out nuclear war, and deepened its commitment to processes of détente before defence.

Tensions re-emerged in the 1980s, particularly after Nato’s 1979 ‘dual-track’ decision to station nuclear forces in western Europe. Though political leaders recognised the importance of this action in countering the threat from Soviet long-range forces, European populations were wary of stoking Cold War tensions. In the early 1980s, anti-nuclear protests increased. The irony was that heightened nuclear fear was one factor that brought the Cold War to its end.

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Has Nato’s cohesion become less sure since the end of the Cold War?

JS: That Nato lasted through the Cold War is a remarkable achievement; most alliances are brief, and many collapse under the weight of their disagreements. That Nato survived the end of the Cold War, and therefore the disappearance of its original purpose, is even more extra-ordinary.

It survived because by 1989 its character had changed. Although its formal structure remained military, its purpose and procedures became increasingly political. Nato has become a forum for debating larger security questions, for co-operation on specific problems, and for trying to resolve difficult bilateral issues (hostilities between Greece and Turkey, for instance). One result of this evolution is a willingness to tolerate differences that no effective military alliance could allow. Because no-one is prepared to impose the discipline that would be required by a cohesive alliance, Nato’s proclaimed plans for greater military effectiveness do not work out.

In 1997, Nato offered a closer relationship to Russia, but the Russians knew they would not have an equal voice

HP: After the Cold War, the ostensible reason for Nato’s existence was gone, but the trans-Atlantic co-operation it had enabled was now so deeply established that nobody considered whether the need for Nato could be over. President George HW Bush and Chancellor Helmut Kohl moved rapidly after the collapse of the Eastern Bloc governments: in the absence of viable alternatives, the reunified Germany joined the EU and Nato.

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Russian governments claimed that, after Germany reunified, they received assurances that Nato would not enlarge further. But membership became part of the processes of democratisation and liberalisation in eastern European countries. In 1997, Nato offered a closer relationship to Russia, but the Russians knew they would not have an equal voice. Russia was aggravated by Nato expansion, by its attempts to include Georgia and Ukraine, and by its interventions in Bosnia, Kosovo, Afghanistan and Iraq.

Was Donald Trump’s complaint in 2017 about unequal contributions from Nato members a longstanding US grievance?

JS: The United States has continually pressed Nato members to increase their military spending. But once again, the secret to Nato’s survival has been a willingness to allow states to opt out of things.

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What other factors – for example, Russia’s re-emergence as a strong power – are affecting Nato?

HP: The crisis in Ukraine in 2014 most upset the testy balance between Russia and the west. The perception in Moscow that Nato opposed Russia’s interests was one factor pushing it towards an assertive foreign policy. Trump’s election seemed to reawaken European anxiety that an American-Russian condominium could leave eastern European countries vulnerable and western Europe facing its security problems alone. As Britain and the EU braced for Brexit, questions about US intentions sharpened the dilemmas surrounding Britain’s future position between Europe and the US, and of the direction of a European grouping.

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In the years of fledgling postwar recovery, the shield provided by the US enabled Europe to take risks. US Nato policy reflected its commitment to defend Europe and to support international institutions, economic co-operation and multilateral diplomacy. If this becomes uncertain, then age-long antagonisms between and within nations will probably become exposed.

Chris Bowlby is a BBC journalist specialising in history. He was speaking to historians Helen Parr, senior lecturer at Keele University, and James J Sheehan, emeritus professor of history at Stanford University

This article was taken from issue 3 of BBC World Histories magazine, published in April 2017, and has since been updated