These people are a threat to the constitution:
Former Secretaries of Defense
Dr. Ashton Baldwin Carter
William Sebastian Cohen
Dr. Mark Thomas Esper
Dr. Robert Michael Gates
Charles Timothy Hagel
James Norman Mattis
Leon Edward Panetta
Dr. William James Perry
Former Chairmen of the Joint Chiefs of Staff
Gen. (ret.) Martin Edward Dempsey
Gen. (ret.) Joseph Francis Dunford Jr.
Adm. (ret.) Michael Glenn Mullen
Gen. (ret.) Richard Bowman Myers
Gen. (ret.) Peter Pace
6. In certain cases or controversies, civilian control is exercised within the judicial branch through judicial review of policies, orders, and actions involving the military. In practice, the power to declare a policy/order/action illegal or unconstitutional is decisive because the military is obligated (by law and by professional ethics) to refuse to carry out an illegal or unconstitutional policy/order/action.
The letter also says that civilian control of the military can be exercised by the judicial branch when an administration’s decisions are challenged, and that a court ruling is decisive because military leaders are obligated by law and professional ethics to refuse to carry out illegal or unconstitutional orders.