TRIDENT submarines, when they are not sailing the seven seas, are based at Faslane, some 15 miles away from Glasgow. Imagine if they were based in Tilbury — a few miles away from London — what political shenanigans that would cause.

Who can be surprised that the Scottish National Party (SNP) has come out foursquare against the presence of nuclear weapons on Scottish soil?

This nuclear pacifism has won support to the nationalist cause and the continuing quest for independence. Yet the Scottish Labour Party at the last general election clung to the view that Trident was necessary for the defence of the realm. Nuclear deterrence remains the name of the game.

But what a game. It is a lethal one of threats and counter-threats, of bluff and double bluff. It assumes that there is a strategic rationality which underpins it.

The US went heavily into game theory in the Vietnam war and yet they ended up literally in the mire. Robert McNamara, one of the architects of this approach, late in life recanted and repented.

Crucially, with nuclear deterrence every decision has to be spot-on every time. One miscalculation, one bad call, one accident and all bets are off. This is the risk we live with every day and by and large have become oblivious to it.

The technology in which this strategy is embedded is of course computerised to the nth degree. Dependence on this admittedly impressive technology raises questions what role humans play, intervening and interpreting.

And there is a serious in-built risk which is not much thought about — nuclear war, with weapons far more powerful than those dropped on Hiroshima and Nagasaki, can only be envisaged as total war.

With these weapons we have the ability to extinguish the human species and destroy the planet. Its end is annihilation. There are no gains to compensate or justify that.

The so-called rationality of deterrence theory is the ultimate absurdity. We are faced with a conventional wisdom about nuclear deterrence that the US sociologist C Wright Mills referred to decades ago as “crackpot realism.”

What is offered as common sense is, at root, an absurdity — and a very dangerous one. In the name of realism we are actually losing touch with reason.

We now have a leader of the opposition who has stated that as prime minister he would not press the nuclear button. Amid the predictable outcry we wait to hear under what circumstances any prime minister would do this. A pre-emptive strike or a retaliatory strike? It all becomes very fuzzy and has never been publicly laid out.

Turning back to Scotland, the Scottish Labour Party now has the chance to rethink its position on Trident and put together a reasonable, non-nuclear defence policy.

In the grand scheme of things it is a secondary matter but would challenge the SNP’s implicit claim to be the voice of the nation — no bad thing in the face of next May’s election for the Scottish parliament. The estimated cost of renewing Trident has now risen to £167 billion and an autonomous Scottish Labour Party should surely take this into account.

Radical theologian Elizabeth Templeton argued that, in the light of threats to our environment, pandemic, famine and desperate poverty, Trident is a relic of a mentality which can no longer be creative.

Its replacement will cost billions of pounds to maintain beyond the many billions spent on its construction.

It is a challenge to our politicians and not least the parliamentary opposition to transcend its “crackpot realism” and bring reason to bear upon this most important of issues.