Another technical mistake in the New Yorker article: it implies that since the missle was armed, the fire could have produced a megaton-sized blast. Not true: the component that undergoes fission in all US nukes designed after 1945 is spherical, and for the component to release significant amounts of energy, the sphere has to be compressed by a very precisely-timed combination of about 20 explosions of conventional explosives (TNT or such). In fact, a new kind of electronic device needed to be invented by the Manhattan Project to meet the precise timing demands.
So, although it is possible for the fire to ignite the conventional explosives, it would almost certainly have not done so in precisely the way needed to activate the atomic components of the bomb -- at least that is what I have read somewhere. (Sorry, I do not remember where -- maybe Carey Sublette's Nuclear Weapons FAQ.)
The worst thing that could realistically have happened is that the fire and a conventional explosion would have spread the radioactive components of the bomb (particularly, plutonium) into the environment, in the manner of a dirty bomb.
Your comment assumes that the weapon was one-point safe, which was not true for all US devices. I cannot remember the source but apparently for many years (through at least the 80's, I believe) many US weapons could have produced a yield if subjected to a fire.
Suppose the trigger device providing the precise timing could misbehave at high temperatures. Or, in the same source I mentioned earlier, it was disclosed that there were wiring paths which could have melted together in a fire and cause the weapon to fire.
So, although it is possible for the fire to ignite the conventional explosives, it would almost certainly have not done so in precisely the way needed to activate the atomic components of the bomb -- at least that is what I have read somewhere. (Sorry, I do not remember where -- maybe Carey Sublette's Nuclear Weapons FAQ.)
The worst thing that could realistically have happened is that the fire and a conventional explosion would have spread the radioactive components of the bomb (particularly, plutonium) into the environment, in the manner of a dirty bomb.