Earlier quoted context omitted.
> Do not confuse disagreeing with someone as that person being morally sub-human If your disagreement with that person is about whether someone else is considered less of a human than they are (by dint of race, wealth, sexuality, whatever), it's probably ok to consider them morally bankrupt on that basis.
No, it's actually not, because people have different moral foundations, and many people value loyalty/authority/sanctity over care/fairness. It doesn't mean they don't care about care/fairness, it just means they don't make it their moral priority. If you refuse to engage with these people and view them all as sub-human there's no path forward for society.
Most people you violently disagree with have probably a different view of fairness than you do, and think that your opinions and goals are plainly unfair, as much as you think the same about them.