The British will hold, a British-Soviet war in the 1980s.

Simply numbers and cost, without the US umbrella (both conventional and nuclear) i doubt many people (both citizens and politicians) will feel very safe so a certain impulse to cover for the lost detterence will exist.
Plus there is the nuclear sharing program of NATO, with the USA out of it it's probable that weapons will go with them and for the reason above the rest of the european goverment will feel more safe if they will be replaced but not only it's very costly but depending on when it happen many nations have signed the TNP so they can't produce national weapon and the sharing program was a legal cop out for it; an inter-european program (basically the French taking the place legally and materially of the americans) will cover the situation and share the cost of the program

That kind of weapon are more for show than effectiveness, at least by the early 80's, as they are pretty vulnerable, while more mobile and light system are the way to go for continental europe; for this reason if the sharing program cease to exist and the americans want their weapons back many goverment will scramble to get new weapons in the quickest way possible and the French are the best option...unless even if isolationist the US goverment decide that the weapons are NATO common equipment and leave them to their allies but as i said, there are pretty strong legal problem with that due to the TNP so much depend when it happen and if it signed by the rest of the NATO members.

The USA can remain neutral as there is an ocean between them and the soviets...the Rhine don't allow this kind of luxury and nobody in Paris want the Soviet as the next door neighbourh; plus it's better to take in consideration that by the early 80's Europe it's already heavily interconnected economically so them taking Benelux and West Germany will cause economic damage so great that there is no incentive in remain neutral.
The problem in any revolt so massive that will block military action...is that  a very big cop-out and frankly come from out of nowhere, some riots? Sure, terrorist attack by soviet infiltrator and red terrorist? It's a given, but unless it happen just after the second world war or during the attempted coup d'etat by the Algerians hardline i don't see that much support for the Soviet or the communist (even local) in France (or in Italy).
Worse, as i said before, by the late 70's many of the european big communist party, italian and French included, were beginning to be very critical of the URSS and openly stated that in case of war they were supporting NATO and not the URSS

I think the problems with a combined European nuclear force are:
a) Timing, as even without political complications it would take years to develop and deploy such a system and I suspect that the Soviets would move before either that occurred or the US elected a different President.

b) The complications politically. Any nuclear weapon with a German finger on any trigger would be a no-no for many Germans and also at the least a propaganda coup for the Warsaw Pact as a number of nations, not just in eastern Europe would be uncomfortable with it. Similarly a lot of nations had already signed the NPT and had significant anti-nuclear movements and the Soviets would make a lot of capital from asking why countries X, Y and Z want nuclear weapons. [You would have groups like CND coming out with their insistence that an aggressive nuclear power will launch nuclear attacks on opponents with nuclear weapons rather than those without them. You never heard them say anything about the massive nuclear retaliation force Japan had in 1945 and how many American cities they hit in response to the US bombings! Its the sort of logical when you let desire for an outcome outweigh all reason and logic. ] Plus there would be the issue of who is authorised to launch nuclear weapons and under what conditions and the danger that the entire system is paralysed by indecision or that decision making is delegated too low and just as say the alliance is agreeing a cease-fire with the Soviets some commander or national official triggers a nuclear exchange.

  As such I could see a system where either/both of Britain and France seek to extend their deterrent forces, possibly with the other nations making a financial contribution but without a significant say, although this would be controversial in those states no doubt.  However a multi-national deterrent I suspect wouldn't be practical.

Overall if we think of the needs of the thread we require:
a) Something to isolate the US from the defence of Europe, at least initially, but having it come in fairly quickly.

b) Something to remove France from play, either having it come under Soviet control or be neutral. I think the latter is marginally more likely, both because it would avoid the question of how the Soviets gained control over a nuclear state and it makes Britain's plight markedly more defensible.

c) Arguably some way for W Germany to be overrun quickly or without fighting so that we have a 'last stand' for Britain and also Britain hasn't lost much of its regular forces and air force seeking to defend Germany.

How about if we have some crisis which results in W Germany accepting full neutrality in return for reunification with the east? This would greatly weaken NATO and possibly cause a de facto collapse with the US withdrawing and France, already slightly removed deciding on a stronger independent nuclear force. Because the reunification involves reserving some influence for the former communist east regime plus the communist cheat like mad and also there is an argument for disarmament for Germany [as obviously there's no longer any east-west tension ] then Germany is largely unarmed and increasingly drawn into the Soviet sphere. The crisis then comes possibly with a staged incident in Germany, prompting claims by the Soviets and their German stooges, of a threatened right wing/fascist coup and a rapid military intervention, then the Soviet forces advancing on into Denmark and the Low Countries. France, alienated from its European neighbours and having received reassurances from Moscow puts its forces on alert and threaten nuclear attack if Soviet forces cross their border but does nothing else and the Soviets leave it alone.

The rump of NATO, probably organised largely around Britain, Italy and the Low Countries as well as Norway and Iceland - with Greece and Turkey's status being unclear, refuse to accept the Soviet actions, aided immediately by Canada and with strong signs that the US will support them quickly - say a forecoming change of President with the President elect already stating he intended to rejoin NATO, decide to fight on. What happens in Italy and Greece-Turkey depends on what Lordroel decides. [Its his thread if I'm not hi jacking it too much]. Ditto with Norway and possibly Sweden/Finland and with Spain. However the most immediate threat would be to Britain as the obvious base for a reforming western alliance to look to rearm and liberate occupied areas. You are likely to have resistance in occupied areas, including much of Germany and possibly unrest in parts of eastern Europe and Russia might also be making a move in the ME which would detach forces and also speed up US intervention.

Anyway a few ideas as to how you might get a ~1980s BoB which isn't totally suicidal for Britain but does give the Soviets a logic for seeking to overrun Britain before aid from N America becomes too strong. It still leaves the question of how they dare risk this in the face of a possible nuclear response from Britain but I don't know what to do about that?

The Germans had 4 battalions of Lance missiles, with access to the US stockpile of W70 Warheads

These are easy to butterfly away, with a bizarre US government that has withdrawn from its most important military alliance.

British and French nuclear weapons are not - under these conditions weak-to-strong deterrence and The Moscow criterion becomes more important, not less.



If Warsaw Pact forces attack France, they will retaliate with nuclear weapons. That is the reason why the French have them, and why they withdrew from NATO command structure. With the Americans gone, they would most likely rejoin NATO!

  Possibly but given the political feeling at the time I think that would be a huge no-no for just about everybody .  Don't forget that if we talking about 1980 this is less than 40 years after WWII and the movers and shakers around much of the world would have been teenagers or children then so they lived through it.  What the Nazis did was such a traumatic experience, not least in Germany that there was a massive opposition to anything that even hinted at a revival of German military power for anything other than clear defensive needs.  IIRC even in the former Yugoslavia mess in the 1990s Germany was very reluctant to send military forces abroad, even for clearly humanitarian purposes.  The suggestion that Germany would have control of nuclear weapons in any form at all would cause massive discontent.

  You could have that as the trigger for why Germany ends up under Soviet control without a major fight and possibly the splintering of the alliance.  If a German government decided to go nuclear it would face huge opposition, both internally and within its allies as well as its eastern neighbours.  Possibly only the US might not be too unhappy with such a move but it would very likely not only cause a lot of unrest in Germany itself but quite possibly split up NATO.  However I think this is less likely than West Germany being lured into reunification in return for neutalisation.