Fear. That’s what Trump/GOP have tapped into. They stoke the fear of an insecure population of conservatives. Fear of people different than you. Fear of being replaced. Fear of change. Fear of not being financially successful. Fear of pointing out the faults of your religion. Fear of lack of control. 

Trump has successfully convinced conservatives that their fears are not the insecurities of a weak minded populace, but someone else’s fault. It’s the immigrants. It’s the liberals. It’s the non-Christians. It’s the rest of the world. 

This is what FDR meant when he said we have nothing to fear but fear itself.