Trump is a very ill man.  During those periods when he is appearing to be engaged, his complexion is florid and and puffy.  Then there are occasions where he is not animated and which he is pale  and appears lost.   At the G20, at one point he started to wander off and had to be redirected by security, or when he had left Air Force I and wandered past his limo to God knows where.  The White House has been turned into a care home.