It’s a given that when giving one’s opinion, someone else may take offense, and be vocal in expressing his or her own opinion.  I understand and accept that, and I certainly have no problem engaging with other people on the same level they choose to engage me on, within reason.  What I do not accept is the notion that this somehow gives anyone the right to drag others into a flame war and target them for harassment.  If you’ve got a problem with me, it’s with me and no one else, not me and my friends, not me and those family members with whom I’m on half-way decent terms, but with me.  Got it?  There is no justification for sending nasty messages to people I’m friends with, calling them up to tell lies about me, intimidating them, or engaging in any other conflict with them, all because you want to piss me off or scare me into keeping my opinions to myself.

That kind of thinking is childish in the extreme, and says more about the mental instability of the person who engages in such behavior than about anything or anyone else.