Dowding, how much will it matter to you if a rogue state supplies a nuclear device that is exploded wiping out a city on your country, or worse yet, some of your family, if the material is traceable? Exactly what difference will the material being traceable make?
Further, it is only traceable IF you have access to and knowledge of some of the material it originated from. If a rogue state had it to begin with, and you don't know how/where they got it, how are you going to trace it? And if those who possessed and supllied it don't care if you know or not, what difference will it make?
The dead will arleadey be dead, the maimed will already be maimed, and the area will already be destroyed. Tracing the origins of the materials used to do it will not change the state of the persons and places already damaged or destroyed. It will still remain the same.