By Lord Hattersley, deputy leader of the Labour Party, 1983-92 (THE TIMES, 16/12/09):

Trident survives. The most severe defence spending review in history — searching for savings of almost £40 billion — ignored the £20 billion that is to be spent on a nuclear weapon that will be redundant before it comes into service. The generals, as has so often been the case, are planning to fight the last war. And the politicians, who must have noticed that the world has changed during the past ten years, endorse the military judgment for reasons that have nothing to do with national security.

The possession of a semi- independent nuclear weapon allows Britain to claim the status of a superpower. Fifty years ago, Ernest Bevin wanted an atomic bomb “with a Union Jack on it”. His successors want a missile that is similarly decorated. Trident is a posture, not a policy.

For 50 years nuclear weapons kept Europe at peace. The deterrent deterred. Whatever the imperial intentions of the Soviet Union — illustrated by Hungary and confirmed by Czechoslovakia — the Kremlin knew that if it crossed the demarcation line that divided East from West, Nato would respond by inflicting what the jargon called “unacceptable damage”. Nuclear submarines, hidden deep in some distant ocean, were the paradigms of that process. If Russian rockets destroyed Liverpool, Leningrad would be obliterated.

The idea that nuclear weapons existed to prevent rather than win a nuclear war was too sophisticated for CND to understand. Fortunately, the idea of deterrence was appreciated in the defence establishments of London, Washington and Moscow. Apparently bellicose, but in fact reassuring, messages were sent by contrived routes from capital to capital. I recall a Ministry of Defence discussion that hypothesised a conventional Warsaw Pact attack on what was then West Germany. We assumed that Nato responded by exploding a small nuclear device in an uninhabited part of Russia. Then we agonised about whether what was meant to be a warning would be interpreted as a sign of the West’s resolve or an admission of its reluctance to unleash Armageddon.

Six years later, in the Foreign Office, I was the constant recipient of messages that read (more or less): “The minister will be aware [I never was] that Academician Vronsky addressed a colloquium in Nisny Novgorod last week. Throughout, he referred to what he called ‘the conflict with the West’ in the subjunctive mood. As the minister will know [I never did] Vronsky’s brother-in-law is an influential member of the Politburo. He would not have signalled a relaxation of tension without official approval.”

The games we played seem silly now. To be frank, they often seemed silly at the time. But they kept the East-West relationship in strategic equilibrium. The messages were sent to me by Julian Bullard, a scholar as well as a diplomat. Similar experts worked in Moscow. I doubt if President Ahmadinejad employs such paragons in Tehran. That is not because Iran is less intellectually inclined than were our Cold War adversaries. Iran is engaged in a different sort of conflict with the West. The new threat cannot be contained by old methods.

It is, we are told, “rogue states” that now imperil our security. Their threat is, by its nature, irrational. Some of the men, we fear, believe themselves to be engaged in a holy war in which martyrdom leads straight to Heaven. Others behave in a way that is clearly not prompted by reason. For the deterrent to work, the opposing forces have to be mutually committed to the rules of the game. Yet it is impossible to imagine the rogue states accepting those rules.

Even so, proponents of continued nuclear capability say that, in an uncertain world, Britain needs to possess a nuclear weapon. Whether they realise it or not, they are preparing not to prevent a war but to win one. That raises complicated questions, which range from the morality of retaliation to the consequences of nuclear fallout for the surrounding countries.

Fortunately, those questions will never be asked. No Dr Strangelove — the evil genius who for half a century CND has been expecting to push the nuclear button — lurks in a Northolt bunker. The rational governments of the West and Russia will never retaliate with a nuclear strike that provides only pointless revenge.

Consider how the “first strike” will come about. Let us assume — wild assumptions are the tools of this trade — that the Taleban or al-Qaeda capture a Pakistan nuclear installation and annihilate a million or so infidels. Are we going to obliterate Punjab? And how will we react to increased nuclear belligerence from Iran and North Korea?

The sensible response is to assume that they just want to be part of the big boys’ club — rather like most British politicians. The renewal of Trident makes it difficult for Britain to denounce nuclear proliferation. Yet, with the explanation or excuse that a nuclear capability is essential to our safety, we intend, over the next ten or fifteen years, to spend billions that we cannot afford. The money could be used to help to reduce a national deficit that will not be liquidated during the years before Trident comes into service.

But, national solvency aside, much of the expenditure could be employed more profitably in other parts of the defence budget. Despite yesterday’s promise of more helicopters and new transport aircraft, our troops on the ground in Afghanistan will still be overstretched. Much conventional capability has been sacrificed.

Britain has a world role — peacekeeping, conflict resolution and fighting bush fires. To finance it even adequately we need to abandon the pretensions of a superpower and ditch Trident now.