As everyone is now aware, the latest approach of President Trump’s political opposition writ large is to insufferably attack his mental fitness.  This is a historic pattern of the left-wing against people they disagree with.  If you disagree with a far-left Marxist your thinking is wrong.
Not accidentally this is the exact same common approach within mainstream communist media; a modern example is China.  Disagree with authoritarian-minded people and the way you think becomes the primary focus of your risk toward them.  Professor Alan Dershowitz puts this into context: