This Christmas, we should give thanks to our nuclear missile submariners

The UK’s nuclear deterrent is often referred to as the Continuous At Sea Deterrent. Inevitably abbreviated to CASD, it is one of the more accurate military descriptors out there.

It is Continuous. Every single minute since April 1969 one of the UK’s four ballistic missile submarines or ‘bombers’ (called boomers in the US) has been on patrol in a location unknown to the nation’s enemies. The first four were the Resolution class (has there ever been a more apt name than HMS Revenge?) armed with American Polaris missiles fitted with British nuclear warheads. These were replaced in 1990 by the Vanguard class armed with the Trident missile, similarly British tipped. The USA maintains 12 Ohio class Trident boats, and likewise is always ready to launch.

The network of resources to achieve CASD is impressive. It includes many things: satellite coverage, undersea sensors, the RAF’s restored maritime patrol capability, the Royal Navy’s on-call towed-array frigate, its route survey and mine clearance and our attack submarines (SSNs). I commanded a frigate that spent time in the Greenland-Iceland-UK Gap detecting and deterring Russian submarines there, partly to rule out any chance that one might get into a position where it could get on the trail of a bomber coming out of Faslane. Earlier in my career, I spent months on end in minehunters, scanning the routes in and out of Faslane to ensure they had not been mined and if not sure, sending down the other type of human who volunteers to spend time underwater to have a look – Royal Navy mine clearance divers.

The US leads much of the international effort in support of this task. When it comes to deep water anti-submarine warfare, unusually, their surface ships are less capable than ours. Of course they have enough SSNs to compensate.

Nations do not go to the huge effort and expense of placing intercontinental ballistic missiles – basically space rockets – with nuclear warheads aboard super-stealthy nuclear powered submarine launch platforms for no reason. One of the key principles of deterrence is assured use. If an enemy can destroy your weapons with its first strike, then your deterrence is diminished. Land and air launched options both require the nuclear weapons to be kept in places whose location is known and therefore targeted. The UK decided, correctly, that the least vulnerable, and therefore most credible, option was underwater and the Resolution class was born.

This brings me to the first myth attached to the deterrent – that it is a waste of money because it has never been used. It has in fact been in use every day since 1969, shaping foreign policy and military decisions along the way. Arguably, nuclear deterrence has prevented superpower-level conventional warfare, which would have been a bloodbath even by World War II standards. And you only need to look at the war in Ukraine to see how Nato and Russia are both trying to avoid the conflict becoming a direct clash … for just this reason. Our nukes work, and they are working today and have done every day since their inception – this makes them very good value.

The second myth is that the patrols have not been continuous and that the odd day has been missed here or there. This is wrong.

A Vanguard class nuclear deterrent submarine returns to Faslane on 11 Sep 2023 heavily encrusted with marine growth, reportedly after a patrol lasting more than six months – @SheilaLWeir

The final myth is that the UK cannot fire its missiles without US approval. This is equally wrong yet seemingly impossible to shake off. Sure, the US builds the actual missiles and if it were to stop, after a period, so would our deterrent (although this technology share goes both ways). But once embarked in our bombers, their use is entirely in the hands of the UK government and the person in charge of the boat. The missiles are rendered more accurate by using America’s GPS satellites, but this is only relevant for so-called “counter force” targeting, against an enemy’s hardened missile silos or the like. Britain does not have enough warheads for this, and would instead be looking to destroy Russian cities: unassisted inertial and star-sight guidance is fine for this.

So that’s the good news – the subs are continuously at sea, extremely secure and operationally independent. But they are creaking.

One of our boats recently came back off the second longest ever patrol, of 195 days, looking decidedly weathered. That her patrol was extended well beyond the ‘normal’ three months is down to hull availability, which is getting worse and worse as the boats get older. There is also mismanagement ashore. Rear Admiral (ret’d) Philip Mathias attributes the delays in getting the next boat ready to “the dreadful performance of both Babcock and the submarine delivery agency, created in 2018 … with HMS Vanguard’s refit in Devonport taking seven years, double the planned length”.

There is also the delay to the Dreadnought class replacement. The 2006 White paper indicated 2024 for the first to be delivered. In 2010 this had become 2028 and by 2015, to ‘early 2030s’ by which time the Vanguards, built to last 25 years, will be 40 years old. Of course, these slippages were all classed as ‘savings measures’.

All of this affects current patrols. It’s not clear how long the boat out now will have to stay on duty but the trend is only going one way. This is not a good thing for either safety or ship’s company morale, both of which are entirely symbiotic.

They are an interesting bunch, our bomber crews. Even other submariners are rude about them (coming from a place of warmth, of course). They spend every hour of every day creeping about very slowly and silently to avoid detection, at immediate notice to be used and yet hoping not to be. They work in relentlessly monotonous watchkeeping routines, with no space, no privacy and the kicker, very limited (receive only) communications with home. They even had to invent their own system of recognition as there were no medals that applied. You can see why many are reluctant to join now, another trend that is getting worse.

One element that captures the imagination is the ‘letter of last resort’ drafted by each new Prime Minister on taking office and then locked deep in the commanding officer’s safe. This is the letter from Father Christmas you absolutely do not want to receive as it is for use if the recognised chain of command is, umm, no longer there.

What it contains is anyone’s guess, and besides, I would be more interested in working out what was left ‘up top’ than reading instructions from someone who, by definition, isn’t there anymore. I would imagine the real utility of that letter is focusing the new PM’s mind on the enormity of the responsibility they have just taken on rather than anything of practical use.

Navies spend most of their time deterring and being ready to act if that fails. The Bombers are the ultimate example of that theory. So far it has worked, making the seemingly large costs of the boats good value in real terms. And indeed the cost is only large when set against the Defence budget: it would be a trivial expense for the health or welfare departments.

It’s a unique privilege of being British or American (or French) to be able to watch Vladimir Putin or his henchmen ranting on Russian television about the possible destruction of London or other places by Russian nukes, and to be reassured just how unlikely that is – as Russia would in its turn have nothing but lakes of molten glass where its cities used to be, if it did launch such an attack. It’s our bombers and boomers (and boomeurs, perhaps) who deliver that reassurance. It’s thanks to them that we can feel safe to enjoy this festive season as best we can.

This Christmas, like every one since 1969, will see a team of Brits keeping watch somewhere out at sea, separated from their family and friends with a severity that happens to nobody else, not even the rest of the Navy. They will probably be the only UK forces that cannot call home on the day. Astronauts have it (far) better.

At the front of their minds they will be focused on the job at hand – remaining undetected and being ready. Not too far back will be wondering when they will be allowed home to have their Christmas.

British submariners have it particularly bad, due to political, Defence and industrial mismanagement of their submarines and their replacements. But any American or French readers should be equally grateful to their own watchful guardians.

We should raise a glass to them this festive season and to their relentless, and relentlessly challenging, contribution to world safety.

Tom Sharpe is a former Royal Navy officer

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