My vote would go to Threads for sure.
Question, it may have already been listed here, but I remember an old movie (possibly made-for-tv) where the US president is in a diner during a nuclear exchange. Vaguely remember the middle east being involved (attacking the US), and their nuclear weapons not working as they had been bought from the US, who had secretly disabled them.... Anyone know what i'm talking about?
I remember watching it late night in the UK, possibly with another film called The Second Civil War. (Which is also worth a watch).