(Editor's note: Kent Harrington, a former senior CIA analyst, served as National Intelligence Officer for East Asia, Chief of Station in Asia and the CIA's Director of Public Affairs.) Whether they blame texting and tweeting, the malign effects of the mass media, or the nation's struggling schools, most Americans would agree that what we say to each other … and how … is sliding downhill. From professors to pundits, the degradation of our public discourse obviously hasn't gone unnoticed. Nor has its recent accelerant, President Trump, who by now has proven he poses no threat to the rhetorical ranking of even the most stumble-tongued among his 44 predecessors. Presidents set powerful examples in our society and politics, including their use of language. Trump is no exception. Unfortunately, from a stunted vocabulary to obscene name calling, his reality show version of the White House has debased rather than dignified presidential speech. It should matter to Americans. For one thing, it erodes the president's influence as a model of our values, such as the importance of civility and well-reasoned discussion in everyday life. In foreign affairs, the effects of Trump's incoherence and barnyard banter are even more significant. In fact, they can be a matter of life-and-death.