A condition that affects some atheists, though certainly not all; primarily the ones who are intolerant of religion. Essentially, they take the activities of the westboro baptist church (or WBC) and try to apply them to all Christians, or even to all religious people. The WBC is an extemist hate group, and it is very important to note that they reject, and are rejected by, all other Christian denominations.
This condition may be unintentional, and therefore born out of ignorance; or it may be intentional, and therefore born out of malice.
Stupid person: I hate Christians! All Christians protest all the time with signs that say "God hates fags", and they always disrupt funerals and tell everyone that they're going to hell!
Smart person: No, moron, that's only the westboro baptist church, and no other Christians. You're clearly suffering from WBC-itis.
Stupid person: What? I don't understand!
Smart person: I know you don't.