“Really? Ever heard of the Kurds.”
Hussein did not target the Kurds because they were Kurds. He targeted them for the same reason the Syrians, Iranians and Turks have been hard on the Kurds: They want their own nation. Even when Hussein gassed the Kurds he only did so because he believed - correctly - that they were disloyal to his regime. The Kurds had formed a relationship with the Iranians - the arch rivals of the Iraqis.
ISIS is different. ISIS wants complete uniformity of religious belief. Hussein didn’t give a damn about religion nor did he care much about ethnicity. ISIS is made up of Arab supremacists who just today were said to be raping Yazidi women in order to end their gene strain of blonde hair and blue eyes: http://www.dailymail.co.uk/news/article-2724658/Were-not-leaving-Yazidis-refusing-come-mountain-300-women-stolen-ISIS-impregnated-smash-blond-bloodline.html
Do you think Hussein gave a crap about any of that?
Hussein used rape rooms, torture cells and brutal killing techniques all aimed to control and manipulate the populous. No different than those used by ISIS. He simply did it for a more secular power than the religious ISIS.