If you've spent any amount of time on the Internet, you've either participated in, or at least been an uncomfortable witness to, unwinnable arguments with mindless bigots. Mindless prejudice is, after all, among the many things the web has greatly simplified. Never before has it been easier to anonymously tell the world about how whichever minority/religion/gender/sexual orientation/phase of the moon is destroying the world! And, if you've spent any amount of time on the Internet, undoubtedly you've noticed that these arguments are unwinnable because every mindless bigot in the universe has the same irrefutable argument against anyone who might question their prejudices.
"You people are all awful awful hypocrites because you're prejudiced against people with prejudices!"
Wait, did I say "irrefutable"? Of course, I meant "completely invalid and illogical and silly". It's like criticising someone who's being shot at for fighting back against their attacker because it makes them every bit as violent and immoral.