Because Killing Them All is Not an Option
Anarcho-pluralism as the peaceful alternative
Hey, anarchists, or really any reader who believes passionately in your political ideals for changing this world: depart with me on a thought experiment.
Your revolution succeeds. Through whatever means you think it possible, your fellow ________s have defeated the authoritarian/fascist/totalitarian forces and are ascendant. You, of course, know that your side will not rule in the same ruthless manner your enemy did.
Now what do you do with all these enemies whom you haven't killed or converted yet? The same beliefs that motivated them to oppose you in the past are likely not to be simply cast aside. After all, you didn't cast yours aside when you were out of power. As somebody experienced with dissidence, you know all too well that such people can take a long term view of their agenda and undermine the society you want to build in countless subtle ways.