(Jim Lo Scalzo | Pool Image | The Associated Press) In this Feb. 28, 2017, photo, President Donald Trump, flanked by Vice President Mike Pence and House Speaker Paul Ryan of Wis., arrives on Capitol Hill in Washington, for his address to a joint session of Congress. No natural orator, Trump has nonetheless shown at times that he can deliver a powerful speech that effectively outlines his vision, strikes an emotional chord and moves commentators to declare that he, at last, looks presidential. And then the teleprompter gets turned off.