We still need our nuclear badge

Earlier this month one of the most significant figures in human history, Paul Tibbets, died aged 92. Tibbets flew the plane that dropped the A-bomb on Hiroshima. Ever since, political leaders have faced the immanent risk of the destruction of civilisation through design or miscalculation. In response, every British government has supported the development and maintenance of an independent nuclear deterrent. What were the reasons, how far were they were justified and are they applicable to policymaking now?

A book published last week, Cabinets and the Bomb, by the historian Peter Hennessy, provides a remarkable documentary record of these deliberations. The story is told through declassified Cabinet and Cabinet committee papers, and is supplemented by expert annotations and references to other contemporary sources. It makes clear that, while underlying policy has been consistent, the arguments deployed to support an independent deterrent have shifted markedly. They comprise, in the words of the former MoD official Sir Michael Quinlan, “a set of rationales to clothe that gut decision”.

But the initial gut decision to develop a deterrent was far from irrational. In August 1945 the new Prime Minister, Clement Attlee, wrote a terse memorandum in which he noted: “We recognise, or some of us did before this war, that bombing could only be answered by counter bombing... The answer to an atomic bomb on London is an atomic bomb on another great city.” Coupled with his conviction that “this invention has made it essential to end wars”, Attlee had encapsulated the notion of mutual deterrence by counter-city targeting. There was no necessary reason that postwar Britain, with its enfeebled economy, should then have sought an independent nuclear deterrent. But Nato had not yet been formed, and America's continued commitment to Europe's defence was uncertain. In 1946 Congress prohibited the sharing of nuclear information with any other country. In Cabinet, the Foreign Secretary Ernest Bevin insisted — apparently after a long lunch — that, with regard to the A-bomb, “we've got to have the bloody Union Jack on top of it”.

Considering the party's later temporary aversion to nuclear defence, it is worth recalling that the independent deterrent was Labour's creation.

When he took office again in 1951, Winston Churchill was astonished to discover the extent of his predecessor's atomic programme, kept secret from the full Cabinet as well as Parliament. (“I thought that some of them were not fit to be trusted with secrets of this kind,” Attlee later explained.) Churchill's principal adviser on atomic energy, Lord Cherwell, archly wrote: “I am agreeably surprised that the socialist Government was sufficiently imaginative and patriotic to risk the parliamentary criticism to which this might expose them.” Churchill's Government took the momentous decision to develop an H-bomb programme. The PM's own metaphor in expounding that proposal to his Cabinet colleagues is a piece of social history in itself. The H-bomb was, said Churchill, the “Badge to the Royal Enclosure [at Ascot]”.

Britain had — in Dean Acheson's astute formulation — lost an empire and not yet found a role. But the bomb might confer some prestige.

The independent deterrent has its origins in uncertainty over the transatlantic relationship. The Nassau agreement between President Kennedy and Harold Macmillan, under which Britain bought Polaris submarines from the US, ameliorated (though did not dispel) those concerns. While the Cold War persisted, the case for an independent deterrent thus emphasised the marginal benefits of the UK being a “second centre of decision-making” within Nato, lest an aggressor were tempted to test the US commitment to Europe.

Yet the present Government's case for upgrading Trident appears more geared to national than collective security. Trident provides (in Tony Blair's words) “the necessary assurance that no aggressor can escalate a crisis beyond UK control”. The subtle shift is perhaps surprising, given the recent warmth of transatlantic relations. Mr Blair's formulation is nonetheless probably the best justification for the independent deterrent in our “second nuclear age” — the age that succeeds the relatively stable superpower relationship of the Cold War.

Trident will be operational until around the middle of this century. We cannot know the threats that this country will face over those decades. We ought prudently to expect, however, that nuclear weapons will become the property of the worst of states. We have scant information on the totalitarian nightmare-state and nuclear aspirant, North Korea. We know far more about Iran's nuclear programme, most particularly the sheer unlikelihood of its being intended purely for the generation of electricity. (Enrichment facilities at Natanz and a heavy water plant at Arak — before a single reactor has come into service — make little sense for a purely civil nuclear capability.)

If we give up our independent deterrent, our decision will have no effect on states such as these. They will carry on building. The capital cost of renewing Trident will amount to about 3 per cent of the defence budget, and there is no reason to suppose that the costs will run out of control. The only way to deter a nuclear attack is, as Attlee instinctively perceived at the start of the nuclear age, and as his successors have all agreed, to possess nuclear weapons.

It is the uncertainty of an anarchic international order that has persuaded British governments to maintain the deterrent. That is the gut decision at the heart of this debate. It remains the right one.

Oliver Kamm