If a nuke is launched, are we not able to shoot it down safely?
Apologies for the lack of understanding.
I guess it depends on how advanced it is? So if the anti-missile systems in the UK can't see it?
Type 45 destroyers are being upgraded with some missiles that can be used for ballistic missile defense, though I'm not sure they can intercept an ICBM, probably not.
Unless there is something top secret that can be carried by our ships or that the US has deployed in Europe then I don't think there is much that can be done.
The US does have some ICBM defences though these were developed more with North Korea in mind, it's quite a hard task to solve and AFAIK they'll really need to launch multiple missiles in order to have a good chance of intercepting a single ICBM.
Basically, the main defence is MAD + if that breaks down then simply try to target as many Russian launchers/subs/command centres etc. as possible + hope plenty of them fail anyway.
I think the issue with nuclear war discussion is it's all a bit moot.
If it starts, it's over. For all of us.
Not necessarily, more like most of us.
No one really knows for sure, the immediate aftermath is survivable if you're outside a major city/away from a major military base, obviously big issues with lack of infrastructure etc.. after that.
Nuclear winter is perhaps the next worry, how much of an issue that might be isn't certain. The UK is an obvious target so the main issue for us is just how many Russian nukes can be destroyed and how many might fail, miss targets etc.. if lots get through then sure, UK becomes a post-apocalyptic wasteland, if some get through then massive, massive disaster but not necessarily everyone dead, at least not right away.
Even with a massive strategic strike going both ways places like Australia, New Zealand, Chile etc.. might be OK, though survivors in UK/Europe perhaps would have the best chance with access to a boat unless they have a lot of supplies.