Lol, shrug, and realize Mormons really are a cult.
How would that somehow prove Mormons are a cult? If anything, it'd demonstrate their attachments to the values of compassion, tolerance, humility, and the teachings of their faith. They haven't forgotten what it's like to be systematically persecuted by their fellow Americans for their faith and treated as outsiders in this land. That they would so overwhelmingly object to the bigotry of this demagogue would be more of a testament to the goodness of their faith and values.