This writes Politico.
As noted, the retired Republican Senator John Keel was the second person who "dismissed" the proposal. The first was refused by General Jack Keen - almost immediately after the resignation of Mattis.
Earlier, Trump said that "in essence" dismissed the head of the Pentagon, James Mattis. Also, Pentagon press secretary Dana White said she was retiring.
The American president, during his visit to Iraq, said that he was not going to rush to the choice of the new Secretary of Defense.
According to him, Patrick Shanahan can perform the duties of the head of the US Department of Defense "for quite a long time."