When someone uses the term white fragility, I ask them their opinions on White Women's Tears, chapter 11 of DiAngelo's book, which says white people should not show sympathy for black people because the act of caring about the plight of blacks is centering whiteness. Often, I'll follow up by pointing out the parallels of chapter 11 of Mein Kampf being the most infamous for going off on the jews. There is typically a moment of awkward silence before they change the subject.