There definitely is a place for a stern rebuke, but we have to remember to be coming from a place of love whenever possible. I'm reminding myself this as much as anyone, but it bears repeating.
It is especially true with the demonically possessed / oppressed. The demons feed on negative energy, they want you cursing and getting down on their level saying filthy mean spirited things. What they don't want is a rebuke in love, compassion and self control. They don't want you calling upon that small voice inside the person's heart that is still good. Remember that .
I've had a few interactions with some trolls who were a little beyond the pale, like borderline psychotic and possessed. They will go back and forth with people all day if you curse and are hostile with them. But start telling them about the Lord and salvation, wishing for their deliverance with sincerity, and they often start to change. Some demons are tougher than others, but I've seen these guys go from spewing vitriol non stop to quiet or they start going into hysterics and then leave (the last guy said he was on some sort of psychedelic which is known to open people up to the demonic realm). Strange happenings but it is true that the best way to defeat evil is the truth in love. I see scripture confirmed true more each day.
I'm not against the rope for traitors and known criminals. But if you are interacting with people one and one in a normal setting, yes we are called to act in love if we are God's people (which Ayn Rand was not). And this is a spiritual battle.
You better start beating that plowshare