The title is me rewriting the later part of the upcoming quote so it's under the 200 character limit.
This quote largely summarizes my thoughts on hard issues. Couple it with Friedman's thoughts on public good problem. Libertarianism doesn't have all the answers, it won't lead to utopia. It often seems like libertarians are expected to have the perfect response to practically every issue while taking on a hypothetical philosopher king state.
A quote from Dr. Friedman on the subject of carbon taxes that I think can be extrapolated for pollution and other issues in general:
You are evaluating proposals for government policy on the basis of what they could do if optimally implemented not on what one can expect them to do given the incentives of the people making the decisions—what used to be referred to as the philosopher king model of government. It makes no more sense than evaluating the market alternative on the assumption that all the decision makers in that case will act to maximize social welfare rather than in their own interest. The question is not whether an optimal carbon tax designed and enforced by wise and benevolent economists would produce net benefits—very likely it would. It's whether passing a carbon tax designed and implemented as we can best expect it to be would produce net benefits.