NASA does not have, nor want, nuclear weapons. But when it comes to a particular metric that is part of the Artemis Program to land people on the Moon, NASA guards a particular number like they are trying to prevent outsiders from cracking nuclear codes.
I am speaking of the number of Starship launches required to fuel a Starship-based lunar lander in low-Earth orbit such that it can fly out to the Moon, land there, and return to lunar orbit.
This number has been a moving target over the years. The general response from NASA has typically been, 'We don't know for sure, so we're not going to say.' In 2023, for example, the then-director of NASA's Human Landing System, Lisa Watson-Morgan, told Ars, "We have a general idea, but I’m reluctant to say exactly what that is."