President Trump on Tuesday night gave the first of a series of speeches intended to alleviate Americans' concerns about the cost of living, but spent most of the time mocking the term "affordability" and insisting that Americans were doing better than they had ever done before. Speaking to an enthusiastic group of supporters in a casino in Mt. Pocono, Pa., Mr. Trump plunged immediately into the case that Americans, and Pennsylvanians in particular, were actually doing very well, gliding by the evidence about reduced spending power for the middle class. In a winding presentation that ran for 90 minutes, he episodically talked about economic initiatives, but also wandered into discussions of shutting down immigration, at one point comparing the country's sealed borders to North Korea's.