He under estimates Trump. Trump reminds of all people, Huey Long. When he was shot, the FDR crowd breathed a sigh of relief. FDR could never have out demagogued Long, and Long had given up the white suit and stem-winding style by August, 1935. I have seen a news-reel of a speech he gave at that time, and Huey looked downright presidential. Trump has the ability to tone it down, too, and still come across as strong.
All talk and no action leads to annihilation. The more they speak of Trump in sneering tones of condescension, the stronger he gets.