DISCUSSIONS ABOUT replacing Britain’s Trident nuclear missile system are taking place in government with all the public profile of a Stealth bomber. Officially no decision has yet been taken, though one has been promised during this Parliament. In practice, there is no doubt that Tony Blair or Gordon Brown will commission a replacement for Trident, and the only question is how to do so while avoiding an almighty parliamentary row.

This is an issue that hardly anyone in Government feels inclined to talk about at the moment, even off the record. “I can’t talk to you because I know too much about it,” was a typical response this week. “So far, it’s the dog that has not barked and we will try to keep it that way,” admitted one senior Cabinet minister.

The opponents of a new nuclear missile system — and there are plenty in the Labour Party — are frustrated to have no declared policy to kick against. Some 45 MPs have signed the latest early day motion opposing a replacement for Trident, and not all are the usual Campaign Group suspects. There are former ministers, such as Janet Anderson, Gavin Strang, Mark Fisher and Clare Short. And there are normally loyal MPs such as Janet Dean and Gordon Banks. But, as Alan Simpson, a professional rebel, puts it: “Downing Street have played this very effectively. It’s hard for there to be a groundswell of opposition to something that’s not on the front-burner. There’s enough on the front-burner already to occupy the PLP.”

Mr Simpson is worried that any decision will be slipped out during the summer recess. “Tony Blair has tired of the democratic process and wants to shove as much stuff through with no parliamentary scrutiny or decision-making as he can. I think it’s a farewell gift to the Americans.”

The rebels argue that a decision could easily be delayed and that upgrading Trident now, in the words of one, “would make a complete mockery of the moral high ground position Blair tries to take over Iran”. He added, hyperbolically: “Blair’s own obsession with nuclear power and nuclear weapons makes him almost indistinguishable from [President] Ahmadinejad’s position in Iran.”

There are technical debates over whether the life of the existing Trident submarines could be extended, allowing a judgment to be postponed. But John Reid announced, when he was Defence Secretary, that a decision would be taken in this Parliament. And most ministers agree that this controversial announcement ought to be pushed through in the first two years, long before the next election looms. That means soon. In fact, if Mr Reid and Jack Straw had not been moved in the reshuffle, we might have been arguing about it already.

Mr Blair sees the replacement of Trident as one of the handful of tricky policies that he could see through before he goes, thereby doing Gordon Brown a favour. But would it be a favour? Does Mr Brown want to spend some £20 billion on a replacement for Trident? Even Downing Street is not sure. One source asks: “Is he in favour of replacement? Is he in favour of Tony doing it for him? I don’t know. It would be very interesting to ask him.”

The answer, I am told, is that Mr Brown believes Britain must remain a nuclear power and that the most likely option is a full replacement of Trident. But his mind is not closed to other possibilities that involve ground or air-based launch systems rather than submarines. Whichever is chosen, he believes that the issue must be put to Parliament and debated thoroughly.

Yet it not clear whether the Chancellor would prefer to have this debate before or after a leadership contest. If he comes out publicly now in support of replacing Trident, he risks alienating a large chunk of the PLP, the party membership and the unions — all of which make up the electorate for the Labour leadership. Interestingly, replacing Trident seems recently to have dropped off the list of policies that Mr Blair apparently wants to enshrine as his legacy.

There is a good chance that, if the question of replacing Trident were debated in the Commons, whoever was leader, the Government would win only with the support of the Conservatives. Many Labour MPs joined the Campaign for Nuclear Disarmament in their youth and have not reassessed their views since. For them, this was one of the issues that propelled them into politics in the first place. And the end of the Cold War will have reinforced their belief that Britain should no longer possess nuclear weapons.

The rebels claim that building new missiles and the means to launch them would be unlawful under the non-proliferation treaty. They point out that wars these days are fought with conventional weaponry and that Britain’s military forces are already overstretched. Any extra money should be spent on relieving that pressure, not on a nuclear weapon that is unlikely ever to be used.

But Mr Blair and Mr Brown are convinced that Britain would lose influence in the world if it ceased to be a nuclear power. Possessing nuclear weapons is seen as an “entry charge” to a permanent seat on the UN Security Council. Most important for our self-image, it would leave France as the only nuclear power in Europe.

How the British Prime Minister must sometimes envy his French counterparts. There, the nuclear deterrent is part of the nation’s identity. Even though it is far more expensive than the British one, it remains universally popular. President Chirac may have troubles of his own, but he is unlikely to lie awake at night worrying about how he can get away with upgrading his nuclear missiles.

maryann.sieghart@thetimes.co.uk

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