SJWs are used to being able to start fights and keep the fight going until they start to lose, then say, "Enough!" Because their opponents are "decent" people who give the benefit of the doubt, they will shake hands and walk away -- allowing the SJW time to regroup and attack again later. They're able to use a decent man's decency against him, in other words.

So it scares the crap out of them when they realize an opponent won't allow his own decency to be their tool, but will take them by the throat with the same lack of remorse that they showed him. They're so used to getting away with that that it seems like the natural order to them, and anything else honestly feels "unfair."