I didn't hear about it at the time it was released either but I did see the US kinda version, The Day After, which wasn't quite as graphic but nonetheless considered very graphic for TV at the time. There were more then a few movies about a nuclear ending including ones made for TV and shown on ABC Movie of the Week. It was only later in the mid 2000's I found and watched Threads. But I did find it more graphic then anything I'd seen at the time even then (well except for Fred showing me House of a 1000 Corpses one night shift - omfg).