Do you have doubts about your position?

Back when I was an-cap, there were things I worried about: defense, the environment, provision for the poor. I knew the standard answers for them, but didn't find them convincing. Instead, I basically hoped that we would find the real answers by the time an-cap ideas became practically relevant. After all, I was morally committed to the NAP, so I had to believe answers existed; I wouldn't have accepted "this is morally pure but won't survive in the real world."

Then I had a more empiricist and pragmatist shift in mindset, that I don't want to go into in this thread, and reached a point where I could accept the things I'd doubted as actual fundamental flaws in my old ideas, since that was no longer deeply threatening.

Does anyone else here -- an-cap, anarchist, communist, other -- have similar doubts they'll admit to? Things where you're not sure of the answer, but you have to believe there is one, else your moral ideology would crack and crumble?