Nuclear weapons is probably not the best comparison, but there are very dangerous infohazards where the only thing missing is the recipe. For example, there are

Nuclear weapons is probably not the best comparison, but there are very dangerous infohazards where the only thing missing is the recipe. For example, there are immensely destructive actions that individual misanthropic people can take with low investment. Talking about them is bad for obvious reasons, so I'm not going to give any good examples, but you can probably think of some yourself. Instead, I'll give you a medium example that we have now defended better against. As far as we know, the September 11th hijackers used little more than small knives -- perhaps even ones that were legal to carry in to the cabin -- and mace. To be sure, this is only a medium example, because pilot training made them much more lethal, and an individual probably wouldn't have been as successful as five coordinated men, but the most dangerous resource they had was the idea for the attack, the recipe. Another deliberately medium example is the Kia Challenge, a recent spate of car thefts that requires only a USB cable and a “recipe”. People have had USB cables all along; it was spreading the infohazard that resulted in the spree.