Defense didn’t turn out to be a big issue in the UK’s general election, but the one exception to that was the Trident nuclear deterrent. Most of the main parties are committed to keeping a ballistic missile submarine fleet (the exceptions are the extreme leftist Scottish National Party and Greens), although Labour and the Liberal Democrats have some strange ideas about readiness levels. However, it’s almost certain that sometime in the next decade either three or four new missile boats will be launched to replace the four current Vanguard-class SSBNs.
The UK’s nuclear deterrent has been closely linked to the US one since the Royal Navy first bought Polaris missiles in the 1960s, and that cooperation is as close as ever. In fact, the RN and USN share a common inventory of Trident II missile bodies, with the UK – which contributed to the system’s development costs – owning 58 of the weapons. All the Trident II missiles are serviced by Lockheed Martin in the USA and refurbished ones are sent to the next boat that’s being loaded so most of the missile stockpile has spent time in both British and US boats. There are some differences, of course. The UK arms its Tridents with British-designed warheads, for example. US boats run on “fail safe” procedures including a Permissive Action Link (PAL) system, which prevents the weapons being armed and fired unless a valid unlock code is received along with a launch order. Royal Navy procedures are different; there’s no PAL and submarine commanders have the ability (and, in certain circumstances, the authority) to fire on their own initiative. Still, in general the two SSBN programs are closely related.
This relationship has persuaded both countries to cut replacement costs by jointly developing major parts of the new boats. The bulk of each submarine design will be a national project – the UK is looking at a stretched version of the Astute-class SSN – but both navies will use the Common Missile Compartment. It’s not clear how many launch tubes this compartment will have; some sources on both sides of the Atlantic say twelve, while others say 16. It’s even possible that the compartment will be made up of four-tube modules. There’s definitely still debate about how many missiles will be carried. Right now the UK is looking at eight per boat, which is going to leave some empty tubes.
Or maybe not: One of the more sane criticisms aimed at Trident boats is that they’re single-purpose platforms, an expensive luxury in a time of shrinking budgets, but that doesn’t need to be the case. There’s a lot of potential for dual use. The US Navy has successfully converted the four oldest Ohios into SSGNs, a type of boat traditionally only used by Russia, by fitting seven-round Tomahawk VLS systems into most of their missile tubes. If the Common Missile Compartment’s tubes could swing easily between Trident and Tomahawk, that would make the boats a lot more versatile, and could even make them more secure – a potential adversary wouldn’t be able to tell which boats were leaving harbor with cruise missiles on board, and which carried strategic weapons. Alternatively, one boat could carry a mix of Tridents for strategic use and Tomahawks for either conventional or sub-strategic nuclear strikes. That would create a flexible and highly credible deterrent; right now there’s a grey area where a nuclear response to a major attack is appropriate, but a fully armed Trident with multiple warheads is excessive. A submarine with mixed armament would have the option of hitting back hard without having to cross the strategic threshold.
It will be at least another year or two before the shape of the future Trident boats starts to become clear. Hopefully the designers will take the chance to create some truly flexible submarines that will deliver real value for the money as well as a fearsome punch.
Disclaimer: The content in this article is the opinion of the writer and does not necessarily reflect the policies or opinions of US Patriot Tactical.