I stumbled upon a small news piece about the long standing antipathy between Mr. Obama and POTUS45. It mentioned, that Trump to this day refuses to hang a portrait of his predecessor in the White House (as always has been customary). And it went back to the days, when Trump co-initiated the birth-certificate campaign against Obama. And the classical speech Mr. Obama held at a White House Correspondents Dinner. I think, it is an educational must to watch this video from time to time.