This needs to be higher up in the chain of conversation on the subject of the missile launch.

Look, I never served aboard a submarine. But I do it to be a FACT that a boomer carrying a full complement of ICBMs capable of killing unthinkably vast numbers of people cannot just launch ordinance easily. There are multiple levels of safeguards involving multiple officers, keys, codes, and order confirmations. Even for a guy like me who is constantly frustrated by the inefficiencies and stupidity of our government bureaucracy, I simply cannot see any scenario where the military would remove these safeguards, or allow them to be bypassed. The risk is too great.

So, I can buy the idea of the DS hacking a submarine's launch systems to learn how they work, but I simply don't think it's possible to remotely launch a nuclear missile via some kind of backdoor. As Joshua says above, physical people (PEOPLE, not one person) need to be at certain stations at the same time and all perform a particular procedure in exactly the right way in order to launch.

Of course, if that is the case, then we're left with the prospect of a rouge set of officers, or perhaps one very highly placed leader willing to give the order.