Once a President of the United States has been called a traitor, he either is a traitor or the people who called him that are traitors.
It’s one or the other. Now, we just received judgement on the first proposition, therefore...
(If your IQ is higher than an AOC, you should be able to fill in the blank.)
The Constitution defines treason very strictly, just for this reason.
Without a declaration of war or an armed rebellion, nobody can be a traitor.