The author of the piece couldn't seem to work out what you meant, and may have assumed you were calling HIM a "master of spin". If the intended one-person audience can't discern what the writer is saying- and I've been the writer posting something that others didn't find clear- thar might be a sign that revision should be considered.

If you meant to praise the author, why respond to his request for clarification with what reads as snark? Why not just say "I meant the white supremacists are masters of spin"? Don't you think you owed the author of a piece you appear to agree with at least THAT much respect?