It's good as an exhortation to build a Schelling fence, but without that sentiment, it's pretty hollow. Reading the context, though, I agree with you: it's a reminder that feeling really sure about something and being willing to sacrifice a lot of you and other (possibly unwilling) people to create a putative utopia probably means you're wrong.

"Sorrow be damned, and all your plans. Fuck the faithful, fuck the committed, the dedicated, the true believers; fuck all the sure and certain people prepared to maim and kill whoever got in their way; fuck every cause that ended in murder and a child screaming. She turned and ran..."

(As an aside, I now have the perfect line for if I ever become an evil mastermind and someone quotes that at me: "But you see, murder and children screaming is only the beginning!")