Kya Yazeed ko Galiya Dena Sahi hai By Shk Tauseef Ur Rehman

Most of the people abuse Yazeed bin Mawiya accusing him to be the murderer of Hazrat Hussain (RA) and also abuse those who dont hold the same point of view . in all honesty a muslim's aqeeda ( belief ) must be that if there is even an iota of ambiguity you cant hold someone responsible. But today's muslims have made it a part of their belief that if some one doesnt abuse Yazeed ,he is Nasibi/khariji. even some ahlehadith ulema like Moulana Umar (pakistan) are of the same belief. what i fail to understand is that is it (Waqia e karbala ) part of Deen e Islam ? if its so then it will mean that proprhet Muhammed SAW didnt complete the mission he was assigned by ALLAH SWT ma'aazallah summa ma'aazallah. and if waqia e karbala is not part then why so much Furore and fight over the same? ALLAH swt will decide on the day of judgement who is responsible and punish them all who commited this heinous task.