A co-worker, his military son was killing Konies in Africa (Lawrence Taylor, Lord Resistance Army ) and preferred an all metal handgun. Polymer pistols used to physically hit an uncooperative person, often experienced frame breakage. Son took all metal 1911’s because the 45 ACP round hit hard and the pistol could function after a strong forehand or backhand impact.
As for the nuclear aspect, it would depend on the bomb size. A 100 megaton bomb, the fireball is larger than the atmosphere layer and vents into outer space. I really doubt any polymer pistol would survive that.