“Since he took over on Jan. 1, Shanahan has sought to continue the approach Mattis staked out, regularly voicing support for the U.S. partnership with NATO and other allies. But he appears less inclined than his predecessor to challenge the president on significant strategic military policy moves.”
I think this is a nomination of convenience. Since he has become acting secretary he has kept his head down, not been controversial and hasn’t crossed Trump.
So we don’t have a military man in that position but maybe we don’t need one. Maybe it should always be a civilian.
And once there’s a democratic president again they will probably put a military person back in that position anyway so this is just temporary.