WaPo oped by Ashton Carter, Dick Cheney, William Cohen, Mark Esper, Robert Gates, Chuck Hagel, James Mattis, Leon Panetta, William Perry and Donald Rumsfeld:

Given these factors, particularly at a time when U.S. forces are engaged in active operations around the world, it is all the more imperative that the transition at the Defense Department be carried out fully, cooperatively and transparently. Acting defense secretary Christopher C. Miller and his subordinates — political appointees, officers and civil servants — are each bound by oath, law and precedent to facilitate the entry into office of the incoming administration, and to do so wholeheartedly. They must also refrain from any political actions that undermine the results of the election or hinder the success of the new team.

We call upon them, in the strongest terms, to do as so many generations of Americans have done before them. This final action is in keeping with the highest traditions and professionalism of the U.S. armed forces, and the history of democratic transition in our great country.