You cannot calm their fear. The reason is that they do not want their fear assuaged. No, I am not claiming that it is because they are racist. I am saying they are literally addicted to fear and anger.
Medical imaging of left and right leaning people have literally shown that Conservatives have a larger amygdala than those leaning left. The amygdala is the “fight or flight” center of the brain. The larger the amygdala in any person, the more likely they are to be dominated by emotion.
Though that is absolutely the American tradition. Centrists have just as much continual fear and anger about Trump, Russia, etc. Add to this the media and on one side or the other, MSM provides no rational balance, they feed that addiction every hour of day and night.
The biggest problem is that Americans do not wait to be fed this diet of fear and anger. They seek it out. Every day, numerous times a day.