While the likelihood of the proposed scenario so as NATO capacity for an ex nihilo offensive war had been already addressed and discussed...
But none has been suggested.
And the why makes a huge difference to the outcome. I mean if the scenario is the Warsaw Pact rises up and the USSR has fallen into civil war with Ukraine and Byelorussia turning against Russia, okay perhaps NATO could invade, but any notion that NATO could launch some sort of pre-emptive invasion of a fully prepared Warsaw Pact and the USSR is ASB.
I would like to put forward, for consideration, some scenarios that while admittedly might be near ASB. I believe that wouldn't be entirely ASB, that would perhaps, would help to set the circumstances for that, (IMO, again), such possibility would, at least not discarded beforehand...
But, first for , (at least attempt) to avoid the near inevitable either tactical or strategic nucl to the above ear response to this OP proposed scenario---
And, if it wouldn't be stretching the limits of the posible too much, well into full AB territory...
Let say, that the Soviet State and society known alcoholism and systematic corruption would perhaps extend far deeper and somewhat would affect their capacity to follow their doctrine in this proposed scenario. Or that at least would delay what was, above thread, mentioned, likely strategic interchange, until the Soviets leadership would be able to put back the 'house in order' and the nuclear forces correlation wouldn't be so unequilibrated against them...
So, I think a couple of scenarios that may be or not, interelationed : Somewhat the some desk officer in the Soviet counterintelligence came upon a convoluted Byzantine like scheme for put to test
Codename SUNBEAM/TICKLE loyalty and/or that for avoid his foreseeable defection/flee. Feeding him with a fringe possibility yet credible and so alarming info about that at certain date he should flee back to the Soviet Union and/or if unable to get out from his host nation capital. Causing that his info would either be dismissed, compromising his usefulness/credibility for his controllers. Or that if such info hintings, would lead to the increase in NATO military/US/British/French Nuclear readiness and attempts to check it out, would make is simple to track back to him as the 'leak' source... But it rather would lead to be considered an preemptive Nato offensive...
The second, one, a grimmer one, that may perhaps be happening/developing near simultaneously with the above one, (and in the OP suggested timeframe) that the Polish Communist Regime Politic Police killers (and who planned/ordered it) from Jerzy P. which was a Polish Roman Catholic priest that was staunchly opposed to the regime. Would somewhat perhaps, possible that they or their commandant would have either informed or even sought the Soviet local KGB approbation.
Or got Soviet backing and/or bigger backers among the then Polish Regime. Something that would lead that it in the face of the massive popular support of the late priest demanding that the responsible be found.
Something that's unlikely to OTL, would cause that the Polish Regime either willingly or that they'd be so pressured by the Soviets. Would back the priest killers and unleash a widespread and indiscriminate repression of the Polish population...
And that Pope J. P. II besides to attempt pressure/lobbying among the US and European leaders (so as influencing their public opinion) make constants and frantic calls/pleas to action on the dire situation and suffering of the Polish people.
Or even, that would lead him to take any rash decision, (like the one that he mentioned/threatened to do, IOTL), that would aggravate even more, if possible, the situation. So as the tension between both power blocs and internally in the Warsaw Pact between the Church and the Catholics populations and their governments...
)
