I recently read an interesting piece by Jessi Klein in the New Yorker magazine (May 2016) entitled The Bath: A Polemic. (I suppose it is embarrassing to admit I looked up the word polemic. I had a general idea, but I wanted to know specifically. Google was pleased to advise:
A strong verbal or written attack on someone or something.
Synonyms: diatribe, invective rant, tirade . . .