Some have been and others have simply retired and kept out of the limelight.
He was the president and not a diplomat .
What does Chief of Diplomat mean?
When a diplomat is expelled from the country that he/she is working in, the diplomat is declared persona non grata
The President
chief diplomat
The Chief Diplomat is the President of the United States, who at the moment is Donald Trump. Hillary Clinton is not, and has never been, Chief Diplomat.
Barack Obama
carter
An ex-president is a former president - a president who has left office.
Makes treaties
Makes treaties
chief diplomat