The report I saw said that the United States learned that China thought Trump was about to order an attack on China.  Milley called his Chinese counterpart and told him we were not about to attack China.  Milley was trying to calm them down and prevent a very dangerous situation. 

Now, if Milley intervened in the chain of command in order to prevent Trump launching a nuclear strike in the waning day of his Presidency, that may or may not be treason, but I think that was the responsible thing to do.  If I really thought the President was not mentally stable, and could possibly launch a nuclear strike, I think if I were a brave enough, I would commit treason at that point.  

Absolute adherence to the chain of command was an excuse German generals used in the Nuremberg trials to justify committing genocide.  "I was only following orders."

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