I could have told him that back in September.

If it gets to that point, niceties be damned.

He only gives the command. This situation existed before, during the last days of the Nixon admin. It only gets dangerous when you have crazy people down the entire command chain.

unquestioningly.

If he orders a nuclear attack it's extremely unlikely that someone under him will disobey.
They are trained not to question orders no matter how unreasonable they seem.

After all, if Russian missiles were heading to the US unexpectedly, there would be less than 15 minutes for the president to act to protect the US. The people under him would not have time to question his orders so they are trained carry them out no matter what. The system was never designed to be controlled by a madman.

The Democrats are working on modifications to the system that will have some checks to the president's unilateral power but as of now if the president orders nuclear weapons launched, they will be launched.

I fear that in the future, if Trump is about to be removed from office, he might order missiles launched just so everyone else in the world will be taken down with him. I believe he's that kind of spitefully, insane person.