Elections are usually won based on who does the better job of speaking to the interests of the voters. Sometimes that means appealing to their better angels and sometimes it means exploiting their fears. The exploiting fears route is the easiest because it allows voters to rationalize that their problems are all the fault of other people.

Donald Trump and the other right-wing demagogues around the world who are gaining traction these days have tapped into an undercurrent of anxiety that has been building for years. The people who vote for them are like cancer patients who haven't been helped by conventional medicine and have become desperate enough to listen to any quack who promises results.