Mattis is reportedly 'not happy' the White House is blocking his choice for a key staff position
According to FP, Mattis wants former George W. Bush era Pentagon official Mary Beth Long to come aboard as Under Secretary of Defense for Policy, but the White House is insisting he go with Mira Ricardel, a Trump transition team member who also served in the Bush administration.
This doesn't seem to be a fight over qualifications, however.
Instead, FP reports that one of the issues the Trump administration has is that during the campaign, Long was among more than 100 Republican national security leaders who signed an open letter referring to then-candidate Trump as "fundamentally dishonest" and unfit for office, among other complaints.
Long later walked back the letter's criticism and dropped her "Never Trump" position, telling NPR in November that it was "a moral and civic duty to get behind this president."
Still, the report from FP suggests an apparent "blacklist" is in effect for Republicans who openly opposed Trump prior to the election.
Some other "Never Trump" Republicans told The Washington Post the reasons they were not being called for national security positions was likely due their opposition. Another, former State Department official Eliot Cohen, said White House jobs were being viewed as "lollipops, things you give out to good boys and girls."
Theresa Whelan is currently serving in the role as acting undersecretary.
The undersecretary role isn't the only unfilled job at the Pentagon's policy office. There are still vacancies in the No. 2 spot, principal deputy under secretary of defense for policy, as well as supporting roles covering cyber, space, Afghanistan-Pakistan, Russia-Ukraine, and nuclear and missile defense policy.