There’s no difference between a protester’s mask and a klansman’s white hood. That’s what numerous civil rights advocates and elected officials supporting a mask ban alleged Thursday as they further compared some of the recent pro-Palestine protesters to the Ku Klux Klan. Speakers stood in the shadow of Columbia University — the site of the controversial pro-Palestine encampment in April — on 116th Street and Broadway on June 27 and railed again…