Polaris, Chevaline & the Moscow Criterion
 

From Sir Humphrey….


…..”The realisation that Polaris was going to cease to have any credible deterrent value within a few years meant that when faced with the need to spend a huge amount of money on staying credible, a withdrawal into investing in conventional force enhancements made sense. For financial and technical reasons, the UK possibly came closer to nuclear disarmament in the mid 1970s than we have previously realised was the case.

It is fascinating to consider in hindsight what this means – essentially at one of the most challenging parts of the Cold War, and at a time when difficult decisions were being taken on nuclear rearmament, the Royal Navy was operating a missile system it didn’t want, which could not deliver the mission it was intended to do, and which meant that the UK strategic nuclear deterrent was arguably not worth the paper it was written on, if called on to deliver its ultimate mission.”…….

Chevaline
 

A fascinating piece of research. I remember the first time I saw Chevaline mentioned in an open source, it was in a New Statesman article by, I think, Duncan Campbell. I was sitting in the ante room with a visitor from MoD, a long standing acquaintance. I knew nothing of the project and showed the article to him, he remarked “So that’s got out at last”. This must have been in the late 1970s early ’80s.

Strange times,

YS

Indeed Duncan Campbell was the Julian Assange of the day. I'm old enough to remember it and the obsession with Moscow. The US would have got there before us in any instance and there were plenty of other targets. So was it worth it? Deterrence is always about your ability to strike so as to make aggression unprofitable. So "Yes" IMHO

Are you sure the above isn't a quote from the "Broken MoD Procurement" thread?

Plus ça change, plus c'est la même chose...

I remember Barbara Castle (?) being interviewed on TV and pointing out the upgrade " under a Labour Government, of the Chevalier programme"

Very interesting - and timely from a personal perspective. Just in the final throes of editing a paper for Air & Space Power Review on the UK deterrent, albeit V-Force. Without wishing to spoil the surprise, at the time, the targeting policy leading to the Moscow Criteria was little short of arbitrary and the V-Force’s ability to prosecute it, hopeful at best given a number of factors. (Did I mention I like writing slightly provocative articles for ASPR!)
I’ll be interested in reading Sir Humphrey’s thoughts on the RN’s efforts over the next few days.

I have a recollection of cabinet papers being published in book form aound 15 or more years ago which outlined the underlying argument (or logic) of Chevaline and the issue of Moscow.

As a dilemma it represents a fascinating study in terms of spending a huge amount of money, reducing the number warheads delivered, with the intent of leveraging the delivery of those that remain to their intended target.

At the same one might it shows that how just having an allegedly functional ABM system can benefit you by causing your adversary to spend a lot of money to reduce the number of warheads they can throw back at you. In effect the Moscow ABM defence knocked out a third of UK missiles before they ever went to sea on patrol.

The British deterrent was (and still is) declared to NATO, so they would have had NATO assigned targets in accordance with the SIOP. However, Polaris was capable of unilateral use in the event of a 'supreme national emergency', therefore there would also have been a UK target list as well as SIOP ones. Hitting Moscow was seen as key from the start of the V Bomber days.

The problem was that in the late sixties the Soviets put an ABM system around Moscow. The US Navy replaced their Polaris missiles with Poseidon, which had Multiple Independent Re-entry Vehicles, and the missiles fitted in the same SSBNs and same tubes as Polaris. However, the UK was trying to join the Common Market, and Ted Heath did not want to risk upsetting the French and said 'no' to the idea of acquiring Poseidon - yet another American missile. Although Poseidon was a larger missile than Polaris, the Americans found they they could squeeze it in to the missile tubes in existing SSBNs.

Chevaline was technically ambitious, particularly as the UK had given up both long range missile technology and space launcher technology. There was also concern by the RN that the reduced range of the new system limited the area of ocean that the duty bomber could hide in.

From what I’ve seen of that (sources/commentators such as Brian Burnell and others ) it is indeed an interesting topic…, both in terms of what whether UK Polaris was initially or indeed ever actually capable of performing a decapitation strike on the Soviet government and in later years the attitude of some in the RN to enhancements improvements such as Chevaline.

I'd be astonished if a decapitation strike was ever part of the requirement. The ability to destroy the capital (nerve centre, centre of civ pop) is a different thing.

Well the feeling by some is that the CEP of the early Polaris (as issued to the RN) made it of limited use when it came to hitting hard targets within the Moscow area.

It certainly appears (now) that as a result the US adopted a different philosophy to the use of early generation Polaris.

SLBM CEP were always inadequate for hard target prosecution until the advent of D5 and its guidance system.

Until that point SLBM had always been second strike retaliatory weapons, meant for holding cities at risk.

Anyone seeking a more in depth treatment of the Polaris\Chevaline and Trident story along with a description of the targeting options considered may wish to refer to The Silent Deep by Hennessy and Jinks with particular reference to Ch8 Maintaining The Deterrent: From Polaris to Trident.

As a matter of interest, I have long sought a similar account in English of parallel developments and debates on the French SLBM program. It seems less well publicly documented.

YS

I think that this map might help explain why Chevaline caused concern in the RN leadership:

https://cimg1.ibsrv.net/gimg/pprune....9113448bc8.png

Someone at Severomorsk probably drew that up as well!

YS

Chevaline improved the ability of the warheads to penetrate the ABM defences at the expense of the survivability of the SSBN - a shorter range meant that the area of ocean that she could hide in was reduced.

Anyway, assuming that there are some patient souls out there, I have found an 1982 Masters' Thesis from the US Naval Postgraduate School by a US Navy Lt Cdr - The new British deterrent: strategic planning and domestic political implications.

You've got to admit that getting the sub into the Caspian Sea would have been a challenge, and the Aral even more so seeing as the USSR managed to mislay the water in it.

Yeah, but no, but they wouldn't be expecting us to be there. I do hope I haven't given the game away.

It took forever tho - people had to smuggle in bits in the trousers for local assembly under a great vaulting box ......... Christo designed it a- here's the top secret test in Hyde park

https://cimg4.ibsrv.net/gimg/pprune....108eb9dba5.jpg

I’ve just received my copy and I am already hooked after reading the first chapter about Perisher - “A PRIVATE WAR HAS BEEN ARRANGED.”

Thanks for the recommendation.