The President is an office-holder, not a sovereign - Bernadette Meyler //Harvard L Rev

The President's oath of office is to the laws and constitution.  He/she is not the sole receptacle of the power of the executive branch of the United States government.  Attorney General Barr has embraced the opposite view.  But Bernadette Meyler (Stanford Law) has amplifed the argument tellingly stated by Fordham law profs Andrew Kent, Jed Shugerman, and Ethan Leib.  
Writing in the Harvard Law Review (where the Kent/Shugerman/Leib study appeared) Meyler emphasizes that sovereignty and government must be separated.  The sovereignty of the people is not embodied in the President.  Meyler explains that such a monarchical theory is deeply wrong.  Citing the Fordham professors study she explains:

Fundamentally, Faithful Execution and Article II supports a vision of the presidency that emphasizes its status as an office and rejects the residues of sovereignty. In doing so, the piece speaks to two recently developing literatures on offices. While the first tends to emphasize the constraints on the British king himself derived from thinking of the Crown as an office to be held, the second unearths the significance of officeholding in structuring the English and American polities, including at the time of the Founding, as well as the importance of officeholding within the Framers’ political consciousness.^7××× Taking these two literatures together suggests that the Founders were deeply enmeshed within a social framework of officeholding and that they saw the presidency as one office among others.

The essence of office-holding is that power is not personal.  It is a trust - under-girded by accountability and limitation of power.   The insight has gained importance because not only Donald "I can do anything" Trump, but his lawyers and Attorney General have embraced that view.  And recently appointed Circuit Judge Neomi Rao argued in House Committee v. Mazars that Congressional oversight power - to determine whether a President has breached his/her duty of trust - is an impermissible exercise of Executive authority by the legislature.  Only within formal impeachment proceedings is such inquiry permissible in Rao's view.  Oddly she fails to recognize that the authority to institute removal proceedings necessarily encompasses the investigatory power to examine any breach of the executive officer's duty - whether by neglect, incompetence, or malfeasance.

- GWC