I've learned not to bother trying to reason with the majority of Trump supporters I've encountered in real life or online. It's a pointless task, to be honest. You'll end up flustered because most of them will resort to slander and disparaging name-calling whenever they realize they can't win the argument.
Speaking from five years of firsthand experience, I've often been accused of being anti-American and anti-Christian by some Trump supporters because I oppose Trump and I speak out against him. I have been harassed, cyber bullied, and called a few disparaging names by some Trump supporters too.