It's not simple that violence is bad. In my case, I knew I could always call for backup (my mom) if things escalated. But my childhood friend couldn't because her parents were kind of neglectful. So I didn't look down on her for doing that. But I also didn't want to associate myself with certain lifestyles.
It's a slippery slope mistaking doing your best in a bad situation for excusing something wrong as self-righteousness (in this case, violence. And we can also see it in the recent political healthcare event). And I didn't think I would be willing to deal with the consequences of doing things otherwise.
Though we all do rationalization and moralization to some degree. If they are your main defenses, they don't just come out of nowhere in your 20s. They are things you do as habits. They are who you are and what you have.
So you have people in their 40s, 60s who know obviously they are lying to themselves. They know it and others don't buy it. But they can't admit even to themselves. Because if they admit this rationalization, they will have to admit rationalizations for all past mistakes as well. Especially if rationalization and moralization give them financial or social advantages they had in the past or even continue to benefit from it in the present. What's left of their lives if so much of it is based on false comfort?