M.C.: Progress toward voluntarism will be "piecemeal over decades".Is that bad? It may never happen, but if we don't try we're certain to fail. I think even moderate success at a slow pace in some places would be better than nothing. Due to the internet, the pace of change seems to be increasing. And history is hard to predict, we could always luck out and get a positive black swan or singularity. Or yeah, maybe we'll fail.
M.C.: "Most people don't want it."
Most people, quite reasonably, do not want to give up the familiar to leap into a massive unproven experiment. Most people didn't want the Internet, until they did. Most people didn't want to travel via airplane before the Wright brothers got one to actually fly. If real, existing voluntary institutions work better than coercive ones, people will want them. We need to give them a choice, not just an idea.
M.C.: "Philosophical arguments are a waste of time."
There are certainly limits to what they can accomplish. I am more interested in demonstration projects, in coming up with new alternatives. That is, I want to support existing projects, like bitcoin, and develop additional ones, that provide voluntary alternatives to coercive institutions. At the very least, we need to have practices in place that could expand into popular voluntary alternatives, given the opportunity.
M.C.: Skeptical about "national defense".
This one is difficult. Various people have waved their hands at it, but I don't find them particularly persuasive. The problem is that invaders are not necessarily rational, so being able to make them regret their invasion is not the same as being able to prevent it. OTOH, if Switzerland's defenses are plausible, I think voluntaryists could mount some sort of plausible defense. Note that this gloms together a number of different permutations of the problem. At different stages of the transition, people will have different opportunities and face different risks. The real question is, what makes people feel safe? Current US foreign policy seems to succeed in making many people feel safer while actually increasing their risk. I'm not suggesting we need to trick people, I'm just pointing out how complicated this is.
M.C.: Maybe "private police won't work."
Compared to what? Does the police monopoly actually deliver the goods the public think they're paying for?