They are required to regard the Constitution as the supreme law of the land and the source and authority for all valid laws.

They are required to refuse to obey illegal orders.

They are required to give fealty to the President of the United States, as Commander In Chief of the Armed Forces, pursuant to the Constitution, but only on the condition that the person occupying that office does so legally; e.g., not in violation of Constitutional requirements for eligibility.

If a Usurper gains the office of President, then the Armed Forces of the United States must choose whether to heed their oath and depose the Usurper, or else be forsworn and counted as traitors by all US citizens whose loyalty remains unblemished.

Since the Supreme Court has now prevented itself from acknowledging the question of whether Barack H. Obama is or is not an Article II “natural born citizen” based on the Kenyan/British citizenship of Barack Obama’s father at the time of his birth (irrespective of whether Barack Obama is deemed a “citizen” born in Hawaii or otherwise) as a prerequisite to qualifying to serve as President of the United States under the Constitution — the Court having done so three times and counting, first before the Nov 4 general election and twice before the Dec 15 vote of the College of Electors — it would seem appropriate, if not necessary, for all Executive Branch departments and agencies to secure advance formal advice from the United States Department of Justice Office of Legal Counsel as to how to respond to expected inquiries from federal employees who are pledged to “support and defend the Constitution of the United States” as to whether they are governed by laws, regulations, orders and directives issued under Mr. Obama during such periods that said employees, by the weight of existing legal authority and prior to a decision by the Supreme Court, believe in good faith that Mr. Obama is not an Article II “natural born citizen”.