While I was in the Army, I had to memorize and be able to recite the whole chain of command. It included the Secretary of the Army, all the way to the President.
The purpose was to be able to explain the authority of each in the chain. The President gets his authority from the Constitution and delegates it to each down the chain.
If the chain is broken there is no authority that can be exercised.
So then it's your contention that every order issued by every officer and NCO in the military since January 20, 2008 has been illegal? Issued without authority? And all could have been, and should have been questioned?