Should We Renew Trident? A Closer Look at the Arguments

By Rich Wordsworth on at

The Trident nuclear deterrent argument rages on.  In June of last year, when we wrote this piece on the future, past and present purpose of Trident, the only serious political opposition to the renewal of Britain’s nuclear deterrent was coming from the SNP. The other major parties were in agreement that the future of Britain’s security was dependent on maintaining a fleet of submarines carrying enough firepower to scrub half a continent off the face of the Earth. Organisations like the Stop the War Coalition that disagreed were shouting at a political brick wall stretching from Land’s End to the Scottish border.

Then Labour Party members elected Jeremy Corbyn, former chair of the Stop the War Coalition to be the party’s new leader, and things got interesting. Labour is still, as a party, in favour of the deterrent – but Corbyn’s statement that he wouldn’t push the nuclear button under any circumstances were he elected prime minister threw that position into chaos.

On November 23rd, 2015, the government raised the stakes in the Trident renewal debate with the 2015 Strategic Defence and Security Review – a roadmap for the defence of the UK over the next ten years. The current government doesn’t pussyfoot around its position on Trident and its renewal, calling the nuclear deterrent “essential” and declaring that it “judge[s] that a minimum, credible, independent nuclear deterrent, based on Continuous At Sea Deterrence and assigned to the defence of NATO, remains vital to our national security.”

A day later, Trident and its renewal were debated in the Commons, with the SNP submitting a motion to scrap it (it was defeated).

Today in her first statement as prime minister, Theresa May has announced that it would be a "gross irresponsibility" to abandon the Trident nuclear weapons plan and that there would be a vote among MPs on whether to renew the programme.  We spoke to King’s College War Studies department’s Tim Collins and to the Royal United Services Institute’s (RUSI) Timothy Stafford to see where the arguments both for and against Trident’s renewal hold up – and where they potentially fall down.

For: No conventional weapons today provide as much security as nuclear ones

One of the big contentions about Trident is that the money that will be used to replace it comes out of the same pot used to pay for the rest of the UK military. So unless the government suddenly finds a spare £100 billion or so down the back of the couch, spending money on Trident’s successor is money that could otherwise go on planes, tanks, salaries, and so on.

Image Credit: Crown copyright 2013

Those who are for disarmament argue that those sorts of things are perfectly good deterrents already – in the event of a grave threat to Britain, its new aircraft carriers, F-35 fighter jets and so on, combined with the forces of its NATO allies, could do so much damage to an aggressor state that adding nuclear weapons on top would be an expensive case of overkill.

The question, then, is whether there is something uniquely effective about nuclear deterrence that conventional weapons can’t replace.

“Many leaders on both sides of the Cold War were particularly terrified of nuclear weapons,” says King’s Tim Collins.

“There’s a great story about Brezhnev. He was briefed on the Soviet war plan, on what was going to happen if the Americans launched an attack. Then the Soviet leadership produced a button and told him to press it, like he would have to do in the real thing. He was so absolutely terrified by the briefing he’d just been given that he asked them three or four times, ‘are you sure this button isn’t connected to anything? Are you absolutely sure?’”

Deterrence with conventional weapons may be possible – but the spectre of nuclear weapons may have a special capacity to provoke fear in a way that ultimately makes military aggression against Britain unthinkable.

For: Other NATO countries depend on Britain’s nuclear deterrent

Whether you agree it should be Britain’s responsibility or not, that question of what is unique about a nuclear deterrent also has to be considered from the perspective of other NATO member states, which currently depend on the US and the UK for their nuclear weapons. Without that guarantee, the concern is that dependent states might have to take steps to ensure their own security that would run counter to the UK’s national interest.

“Unlike the French, our nuclear weapons are specifically pledged to [defend] all members of NATO,” says RUSI’s Timothy Stafford.

“So this is a political weapon more than a military one: you are guaranteeing the security of other states… Convincing [other NATO states] that they don’t need to go down the nuclear path themselves, they don’t need to ally with Russia and they can remain Western-leaning and pro-EU and pro-NATO… You can’t guarantee that so credibly with conventional forces as you can with nuclear weapons.”

For: Even if we don’t need the deterrent now, we might need it in the future

The assumption in the pro-Trident argument is that a nuclear deterrent safeguards us against an uncertain future – providing what David Cameron and George Osborne have referred to as “the ultimate insurance policy”. But that’s a claim that bears closer inspection.

“Lots of people claim nuclear deterrence works,” says Collins.

“They see lots of evidence for it from the Cold War. [But] there’s a problem in how you prove a negative. How do you prove conflict didn’t happen in the Cold War [because of nuclear deterrence]?”

It’s also worth looking at how the usual baddies in a nuclear apocalypse scenario usually behave. Russia has been poking at Europe recently in its seizing of Crimea, but has stopped short of a full invasion of Ukraine. Its recent probing of Turkey’s airspace led to one of its jets being shot down. If some future aggressor decided to threaten Europe, there’s a growing body of evidence that a slow escalation (rather than an all-out attack) provokes a softer response.

“Nuclear weapons [don’t] deter all culprits,” says Collins.

“Obviously, Britain was attacked in the Falklands, despite having nuclear weapons. Israel has been invaded, despite their having nuclear weapons. I don’t think they’re a panacea for everything. But there is a certain logic to deterrence in certain circumstances that I am persuaded by.”

For: Scrapping Trident will cost jobs and skills, and prevent us from redeveloping nuclear weapons in the future

Pro-Trident Labour MP John Woodcock (who it pays to bear in mind is the MP for Barrow and Furness, where the Vanguards were built) has claimed recently that scrapping Trident and its replacement will cost 13,000 jobs across the UK. The know-how of those working at the forefront of British naval technology may be transferable to other areas, but the farther-reaching concern is the hands-on knowledge of how to build the submarines and the weapons.

“[Giving up the skills] is essentially saying, ‘not only are we getting rid of the nuclear weapons that we have, we are eliminating our capacity to build nuclear weapons as well’,” Stafford says.

“And that requires a much higher level of certainty about the kind of threat environment you are likely to face in the coming years. It’s [a valid] argument from a disarmament perspective, but it raises the bar for making it a persuasive argument. You’re essentially saying, ‘Not only do we think that the future… is such that we don’t need these weapons, but we think it’s unforeseeable that we might need them in future’. And that’s a harder case to make.”

Against: The money could be better spent elsewhere

One of the big headlines in the SDSR was that the cost of Trident over the next ten years had jumped from £25 billion to £31 billion – with an extra £10 billion put aside to provide padding against further cost overruns. However, supporters of Trident’s renewal make the case that, while the £41 billion figure may look huge, taking that money and spending it on, say, conventional weapons wouldn’t get you very far.

Image Credit: Crown copyright 1997

“The amount of money you would save [by scrapping the deterrent] would be very, very small,” says Stafford.

“The UK spends a certain amount of funds on Trident, which is necessary to keep the system going. If you were to cancel the Trident programme and put that money into conventional forces, it wouldn’t actually go that far. It wouldn’t be a step change in terms of what we have at the moment. The price tag looks huge – you always hear these figures like [the predicted lifetime cost of] £90 billion – but spread that over 30 years… is three billion a year. The defence budget is already [about] £40 billion, so adding another three will not really make a huge difference for the conventional forces you have.”

If the UK were to scrap Trident and the Successor programme, that wouldn’t even mean all that money could be spent on something else instead – just getting rid of something as big of the Trident programme comes with costs attached.

“Sometimes it is portrayed as an either-or situation,” says Collins.

“Some people who oppose Trident, like the SNP, sometimes say, ‘well, if we didn’t replace Trident, we could use the money on something else’… [But] decommissioning the warheads, getting rid of the fissile material… That would in itself have a financial cost. So that [money] wouldn’t be necessarily available to go to conventional capabilities.”

Against: We could have a cheaper nuclear deterrent, or scrap and restart the programme when we need it

The point of having four submarines that carry nuclear weapons is that it gives us the ‘continuous’ part of ‘continuous at sea deterrence’. But why not just keep one or two submarines in port, and put them to sea as and when the situation calls for it? If you think an enemy is about to do something nefarious, send the subs out pre-emptively.

The first and most obvious problem is that if your submarines are in port (or indeed if you keep your nuclear weapons in silos, planes or on mobile launchers), your enemy knows where they are. In a real doomsday scenario, that would make them priority targets for any aggressor.

But the more pressing problem is what’s known in international relations as ‘signalling’.

“Imagine you’re watching Britain’s submarines via satellite, you’re in a period of tension, and they notice all of a sudden that Britain has put its submarines at sea,” says Collins.

“What signal does that send? At the very least it says, ‘we’re not confident in this situation’. At the worst, it might send the signal, ‘Britain is preparing to use its nuclear weapons – it’s sent its submarines to sea so we can’t sink them.’”

The same argument holds true for ditching the nuclear deterrent, but maintaining the ability to get it back if the security situation deteriorates.

“Let’s imagine Britain got rid of its nuclear weapons, but kept the option of getting them back in a crisis,” Collins continues.

“Let’s imagine then you’re in a crisis with a country, you decide, ‘OK, let’s rearm, let’s have nuclear weapons’. What kind of terrible and destabilising signal would that send to your opponent? ‘Look at Britain, they obviously think the situation has gone so bad, they’re now redeveloping nuclear weapons’. I don’t think that option is necessarily on the one hand as realistic as some people think it is, and on the second hand, there are real strategic dangers in there.”

Against: Giving up Trident sets a good example to other nuclear-weapon states

Britain is committed under the terms of the Non-Proliferation of Nuclear Weapons Treaty (NPT) to work towards a world free of nuclear weapons. So what if Britain were to ditch its nuclear arsenal altogether? Wouldn’t that give us the moral high ground and increased credibility where it comes to convincing other states that nuclear weapons aren’t needed?

Well, it depends on who we’re trying to convince.

“I’m sceptical of how much [getting rid of Trident] is going to matter in terms of getting other nuclear weapon states to get rid of their nuclear weapons,” says Collins.

“I think every country that has them has their own rationale for possessing them. Some are strategic – think of the balance between India and Pakistan, say, or Israel’s position in the world. I don’t think Britain getting rid of its nuclear weapons is going to make a difference to the value they perceive in having nuclear weapons.

“More generally, it would send a positive signal – the third state in the world to acquire nuclear weapons decides unilaterally to disarm. A lot of people in the disarming community would agree that was a positive, and there would be fewer nuclear weapons in the world, which is probably a positive in its own right. However, whether or not that’s actually going to lead to substantial reductions in other nuclear weapon states is a question mark.”

Stafford is less convinced by the moral argument.

“I think the moral argument will never wash,” Stafford says.

“The reason states have nuclear weapons is that they think need them for their security, and you can make all the moral arguments in the world, but fundamentally you’re having a different conversation from who you’re trying to influence.

“The broader argument if you want to make that case – and I’m not persuaded by it – is, ‘look: we gave up our nuclear weapons and it hasn’t negatively impacted our security’. And then you would make the case that the UK has proved that you can give up nuclear weapons and it does not negatively impact your security.”

So, what should we do?

Something that sometimes gets lost in the discussion of nuclear deterrence is that all parties (political and individual) are, fundamentally, after the same thing: security. Nobody arguing for Trident and its renewal is doing so because they think nuclear war would be a good thing; no-one arguing against is doing so because they think the world is safe. People are arguing both sides of the nuclear deterrent because they believe Trident will be a key factor in the UK’s security in an uncertain future. Whether Trident adds to or guards against that uncertainty comes with no easy answer.

Lead Image Credit: Crown copyright 2010


Tim Collins is a doctoral candidate in the War Studies Department at King’s College London and a member of the Centre for Science and Security Studies research group. He is researching the British nuclear experience and small nuclear arsenals.

Timothy Stafford is a research analyst at RUSI researching nuclear proliferation, deterrence and US foreign policy. He is the coordinator for the UK Project on Nuclear Issues.