Denial

signing of Versailles Treaty  (June 28, 1919)

One (and there are many) ways  to explain the phenomenon of Trump is denial. Climate change is a hoax. Even as the rivers overflow and the forests burn away, the easy thing is to say it isn’t happening, to wish it away. That's why gaslighting Trump's favorite rhetorical device. The same thing happened in Weimar Germany. In that case the villain was the Versailles treaty with its onerous sanctions. Hitler's Willing Executioners is the title of the Goldhagen book. The Germans particularly the lumpenproletariat, who paid the price economically,  were on board with a messianic unifying message which blamed the Jews. You don’t have a Trump or for that matter a Jim Jones, unless you  have followers.