But when even the policy is secret, it is totally beyond even the possibility of democratic control.
Jump forward to the modern day, when the details of the crash are accidentally released with a bunch of other declassified information. It turns out that the flight had absolutely nothing to do with "National Security", it was just a routine flight in a plane with a poor maintenance history. The government was just covering their asses to avoid paying out for wrongful deaths, and bullshit so hard they created a legal precedent.
But launching nuclear missiles is a command decision so the weak point in the system is the means by which an order to launch is authenticated. And whatever secret tokens are used in that process, those I want as few people as possible to know (ideally zero).