Nice Article Richard.

Regarding the ideas expressed here:

“Mill defended freedom of thought on several grounds. First, we should accept the fact that none of us can claim an infallibility of knowledge or a final and definite insight into ultimate truth. Thus, we should value and defend liberty of thought and argument because a dissenter or a critic of conventional and generally accepted views may offer reasons for disagreeing that correct our own errors of knowledge and mistakes in judgment about the truth of things.

Second, sometimes the truth about things exists as half-truths held by different people, and through controversy the truth in the parts can be made into a great unified truth of the whole.

And, third, even if we are really certain that we have the truth and a correct understanding of things, unless we are open to challenging and rethinking that which we take for granted, our ideas and beliefs can easily become atrophied dogmas. The people in each generation must be taught to think and reason for themselves. If ideas and beliefs are to remain living and meaningful, people must arrive at their own conclusions through reflection and thought.”

I see a contradiction with the idea expressed here:

“Anarchocapitalism as the Only Possible System of Social Cooperation Truly Compatible with Human Nature.”

This is a universal truth asserted by de Soto following the Rothbardian conception of Anarchcocapitalism (http://mises.org/daily/3791)

This sentiment is essentially not different (in its fundamental thesis of “the one true system”) than other political/religious ideologies that claim special knowledge of a universal truth.

This is clearly incompatible with what you convey from Mill:

“…we should accept the fact that none of us can claim an infallibility of knowledge or a final and definite insight into ultimate truth.”

Since you single out Rothbard for special mention, I believe it is appropriate to point out the incompatibility of these two visions.

In my opinion, this is not the same vision held by Mises, who wrote in regard to political self-determination:

“…the right of self-determination of the inhabitants of every territory large enought to form an idependent [political] administrative unit. If it were in any way possible to grant this right of [political] self-determination to every individual person, it would have to be done.” (liberalism, p.109)

This vision is not the same as Rothbardian AnCap wherein: “…the basic Law Code….would have to be agreed upon by all judicial agencies… Any agency that transgressed the basic libertarian code would be open oulaws and aggressors.” (Ethics of Liberty, 236-237)

Since you singled out Rothbard for special mention, it should be pointed out that the liberty envisioned in Rothbardian An Cap applies only to the liberty to choose the private protection agency of one’s choice as specified in AnCap theory. This liberty is not envisioned to apply to the individual’s right to choose societies (political administrative units) other than AnCap, which society is held by traditional AnCap adherents as “the only possible system truly compatible with human nature.”

Mises presents us with an alternative vision.

For a moment I thought “It’s 150th Birthday” was bad grammar, until I realised that the apostrophe might not be for the more obvious missing letters of the ungrammatical “It[ i]s 150th Birthday” but for “It[ is it]s 150th Birthday” – the same way “potato’s” is an unconventional way of writing the plural of potato but is actually accurate, standing for omitting an “e” which really is there in the plural of that word.

…it should be pointed out that the liberty envisioned in Rothbardian An Cap applies only to the liberty to choose the private protection agency of one’s choice as specified in AnCap theory.
I’m not going to try to defend “Rothbardian” Ancap, just ancap in general. PDA’s are often mentioned when talking about anarcho-capitalism, but I see PDA as just a language “shortcut” for the alternative to the government provision of these services.
In reality, the arrangment of services and organizations will depend upon the market, and what people prefer to buy. Given the increase in bureacratic overhead, it seems unlikely that, without government privilege, large, vertically-integrated, “corporate-like” entities would be the main providers of private security. Instead, I imagine it would be many more smaller organizations, including separate organizations for different functions (i.e. arbitration, private security, private investigation, etc. as separate companies) with contractual agreements with associated companies for the other services.
Moreover, security in a free society would encompass many different things, not just these companies that provide certain services, but anything contributing to security, including locks, security lighting, fencing, dogs, gun ownership, mace, gated communities, neighborhood watches, etc., in addition to the more pervasive but harder to quantify security provided by a society that truly has free trade and greater opportunities for individuals to prosper and benefit from their efforts, and thus less reason to turn to crimes or vices to deal with the difficulties of life.
In short, the total array of security provision (and justice) in an anarcho-capitalistic society is much broader, diverse, and far more comprehensive than the term “PDA” suggests.