Zen: We are allowed some confusion over US/USSR reaction to "small nuclear Forces...dangerous, expensive, prone to obsolescence and lacking in credibility”: SecDef McNamara, 1962 chose to tell PM Macmillan that he alluded to CDG's nascent Force de Frappe, but there was then only one "small Force". UK's was integrated with USAF/SAC from 1/7/58, into USAF/USN/RAF SIOP 1/4/61, then into NATO/Saceur's Plans 23/5/63 (oddments declared to CENTO/SEATO). I don't suppose the Sovs. had much concern as to whether UK's role in Moscow rubble was to make it, or to bounce it, following-up US ICBMs/FBMs/SAC.
UK spent on all this duplication in part to buy insurance if NATO disintegrated - if a US President chose not to stake DC if Sovs rolled to W.Berlin, or onward. But that was illogical: UK voters, MPs, even Ministers, did not know of the US-dependency of all our Sunshine...but Sovs did. I doubt they ever bothered to draft a Plan to respond to a solo-UK Threat, nor to launch on us, alone. Krushchev blustered at Suez, but bluster was all there was. By the time he had some real sabres to rattle, he knew we were part of a team.
Big Charles had quite different logic in his solo-nuke spend: Force de Frappe was initiated 1954 by Mendès-France, confirmed 1956 by G.Mollet, given highest priority by CDG 6/58 enraged by Krushchev’s threats during Suez, which he chose not to dismiss as puff. B.Goldschmidt,Atomic Rivals,Ritgers,90,Pp.214/6,297,357. He later told Ike: “I have to be unbearable on my own ({just be yourself, I hear you cry} In) order to respond to an invasion of W.Europe (with no Threat to US) I shall use it. (I must) possess the necessary means to change into a nuclear war what (USSR) would have liked to have remained a classic war” J.Lacouture,de G,Harville,91,P368. D.T.Thorpe,Eden,03,Chatto,P275 has Eden sourcing CDG's Anglophobia to Mrs.Churchill 28/11/42, arguing with him over Adm.Darlan, that nice man.
I prefer this to explain his nuclear spend: if UK felt ravaged by McMahon - a cause for Attlee to spend, solo - then yet more so for France: did CDG know of advice, Lord Anderson (Minister responsible for Tube Alloys) to WSC 7/43 before Quebec Agreement putting UK in Manhattan: “moral obligations (US/UK are) indebted to certain French scientists for having been the first to attract our attention to this programme. PM took no account of this whatsoever.” Goldschmidt. It is on such human frailties that vast resources were assigned, to France's economic detriment, v.say, Japan, W.Germany, to deploy 10/64-76: 36 Mirage IVA/(AN-11/AN-22 bombs); 1971-79, 5 Le Redoubtable SSBN (16xAerospatiale M-1/2 FBM); 1974-93, 70 Aérospatiale S-2 Pluton SSM; 8/71-6/80, 18 S-2, 30 Hadès SRBM.
Despite CDG's own bluster about pointing his Force to all azimuths, despite leaving certain NATO forums in 1966, France stayed involved in high policy, and, I submit, would have been right there with us, if the balloon had ever gone up. He owed us, after all: his Frappe was not as solo as he asserted: G.Prins (Ed.), Defended to Death, Penguin, 1983,P.340: “France benefited from (July,58 easing of McMahon Act) with an import of enriched uranium for its prototype submarine reactor in 1959.” 10/62 “US agreed to sell a nuclear sub (sic: =reactor) to France”. I.Clark, Nuclear Diplomacy & the Special Relationship,OUP,94
US helped both small Forces. Hence my first post: as we scurried post-Skybolt, Buttler/Gibson, BSP IV, has many sketches of devices - Polaris on Vulcan, Blue Water resurrected, on TSR.2. Was it not all simply noise in the pricing negotiations that led to the (hugely favourable) Polaris Sales Agreement? We even got our Levy waived - our contribution to FBM R&D cost was offset, as "rent" for Diego Garcia.