I too liked the description of the "Battle of Whitby". One of the things I like about "Protect and Survive" generally is that it does show that people retain their human qualities no matter how dark the circumstances - contrary to popular opinion, even a nuclear war wouldn't be the end of civilisation, just a setback. We'd bounce back eventually.
I also liked the dark humour of the inmates at the hospital cheering the arrival of the bulldozers to dig their graves.
Re the nuking of Argentina - a completely bonkers, over the top reaction to the incident at sea, which would be a bad idea for several reasons. Apart from the immorality of killing hundreds of thousands of civilians in retaliation for a small scale attack by military personnel, it's going to make the UK a pariah nation - it'll probably put the kibosh on any prospect of Britain receiving any aid from undamaged countries. I could imagine it causing a potentially dangerous split in the surviving UK government - members of the cabinet decide that the PM's become unstable and needs replacing, or maybe the King tries to take control? Or both? When Argentina gets reorganised, could they retaliate? Not with nukes obviously, they don't have those, but Britannia no longer rules the waves, so in principal what's to stop the Argies loading up a few warships with troops and striking at Portsmouth? Our side probably wouldn't even know they were coming until they appeared on the horizon, so conceivably they could put the British government out of action. Or, more subtly, infiltrate a Special Forces team and assassinate the PM. Apart from anything else, the UK can't have many missiles left after the Exchange. Personally, I'd be wanting to hold what was left in reserve in case it turns out the war's not completely over after all (Soviet missile silos were designed to be reloaded) or in case some other serious trouble should arise in the future. It's not like there's any serious prospect of acquiring more nukes for decades to come.