The copy editor is in.
I'm presenting occasional posts on the use of English,
not to be pedantic but just for the fun of language.
I hope I don't catch a lot of flak for saying that "flak" is the appropriate spelling for an attack or opposition, and "flack" is a person who specializes in publicity.
Hard to imagine they'd get confused, then, but I think English speakers don't like the odd c-less spelling of flak. That makes sense, because "flak" is German, and unusual German at that. It's an abbreviation of Fliegerabwehrkanone (anti-aircraft guns), so it was adopted into English from WWII, and became metaphorical sometime thereafter. For another literal use, think "flak jacket."