Donald Trump just tweeted that being at Madison Square Garden Saturday night was "a little bit like walking into a Trump rally" ... which means he was impervious to the boos as he entered the arena.
Trump had to know the venue would be as polarized as the U.S. Capitol ... just by the demonstration outside MSG as he arrived. Donald Trump Jr., who accompanied his dad, called reports of booing "bullsh*t." He noted UFC Prez Dana White called the President's entrance electrifying. Eric Trump was also on hand for the fight.