Try to plough through any of the behavioural, rational-actor-driven treatises on nuclear deterrence – say, H.Kahn, On Nuclear War – and the head hurts. It’s like astronomy.

So, assume that I am Leader of the Realm, and must defend it against…well, inherently, I know not what, but anything and everything. I have been taught that WW1 was triggered by a brief window, where the balance of Central Powers’ Dreadnoughts v. UK/France’s left the outcome open to doubt. And that WW2 was provoked by the brief window Hitler saw before Russia’s Pe-2, UK’s Warwick/Stirling/Halifax/ Manchester, and France’s Consolidated LB-30 Heavies would Paralyse his transport/production. And that in Berlin, 1948 and Korea, 1950, Allies had little more than bluff to deter Stalin rolling onto Antwerp (“shoestring” US inventory, 50 inoperable Mk.3 Bombs, 1948, changeover 1950 to Mk.4, maybe 250; dodgy B-36 readiness).

Never again! What to do as my hulls rot?
Option 1: rollover, talk to my Threat, cause him to see sweet reason. But M.Foot and N.Kinnock lost 2 Elections that way, 1983, 1987.
Option 2: delegate defence to US and hope their interests and mine always align. Ah.
Option 3: invent my independent system. But I can’t even do health software.
Option 4: European Multilateral Force. Monty called that poppycock in 1962. All true, I feel.
Option 5: I have an Agreement with US from 12/1962 which gives me access to Polaris/SSBN and its successors (the sense of this – exact phrase not to hand right now). The 1981 successor has been very cheap. Evidently USN is to lead the 2020 successor, so, I’ll stay on board, because it is cheap…and I do not risk any consequence of having no nuclear shaft in my quiver. Just do it. Next!