Pontius, I'd say Dame Thatcher would have been more likely to not balk at the prospect. But I don't know for certain.
What bothers a lot of people about the nuclear deterrent game is that it very much resembles a poker game with some cards up and some hold cards.
And a lot of bluffing.
Gen:
We aren't in as much disagreement as one might think, but I do not agree with you here.
If he knows you can and will respond in kind, he will be deterred.
If he knows you can, me
may be deterred.
Nobody
knows if you will. All anyone knows is if you can or can't.
That is how having in one's possession working kit establishes the baseline for deterrence.
Do I want to risk him/her hitting that button?
I think we can agree that in Saddam's case, his only "WMD" of known quantity and/or use was gas, and the fear some folks had was that he was trying to establish a non bluff nuclear deterrent. Hence my point on his being a paper deterrent, which isn't a deterrent at all. He didn't have working kit.
If one looks at the efforts in Iran to establish working nuclear weapons, I will ask (returning to the opening post and this thread's actual topic) ...
Does Iran establishing the capability change the UK's nuclear deterrent posture? If not, whose does it influence?