I've been reading some books on physics lately, and it struck me yesterday as I was driving and trying to explain the whole quantum concept to a friend that perhaps liberty and freedom are in a much similar situation; to wit, that there is a "quantum level" of liberty, which proceeds from the fact of self-ownership, and a "macro level", which proceeds from the need among human beings for formal structures designed to prevent the acquisition by anyone of sufficient power to truly threaten that individual liberty. Just as with physics, it wouldn't give us a unified theory of liberty, but it would provide a coherent approach to dealing with the tensions generated by the need for governance of whatever sort.
By governance, I don't mean government, although that is one form. Governance includes any power structure designed to provide checks and balances to encroachments on liberty; perhaps the prime example in American history being the Underwriter's Laboratories, which brought regulation and quality control to manufacturing before government ever got into the game. Another example is corporations, where people pool their resources and risks; a third unions, where people pool much the same thing. Reaching back into history, in the time of the fictitious Three Musketeers, the church served as a balance to the king, and the king to the church. Jumping to the US Constitution, the right to trial by jury was included as a check on unrestrained government, and the different levels of government as checks and restraints on each other. For that matter, not-for-profit groups such as my new one, which focuses on conservation in a way that includes trail work and even installation of rain shelters, specifically for one (very large) county park and its ecosystem, can serve as governance, by taking over care and management of public resources in a way that is not government-dominated.
Basic libertarian theory as it stands errs in applying the non-coercion principle in two ways: first, with the a-priori assumption that only physical coercion, i.e. the threat or application of physical force, counts, and the closely related assumption that thus only government can be an enemy of liberty. That might be reasonable if human beings were merely physical entities with no soul, which is to say without emotion, without imagination, but we are not. Since we are not, coercion can come from any entity with power to give the appearance of a threat to individuals' well-being, whether that entity be a church, a professional association, an organized crime gang, a corporation, a political party, a media empire, a union, a tribe, or any other organization humans might invent. In what passes for libertarian thinking these days, the glib assumption that if government is shackled and hobbled, then individual self-interest will work together to create a paradise rules all discussion even when -- or perhaps especially when -- unstated. But it's a very simple matter to look at the world around and see that the assumption is false. At that point, we are faced with the problem physicists face with quantum theory: it describes well the interactions of discrete entities on the individual level, but it fails to give guidance on the large-scale domain.
To employ a common standard from logical thought, current libertarian thinking, that government coercion is a danger to liberty, provides a condition that is necessary to uphold liberty, but one that is not sufficient -- a matter strongly indicated by watching children in their early teens band together to coerce others into conformity.
Finally, just as in physics rules for the behavior of large amounts of mass and energy cannot contradict quantum rules, neither can the rules for large masses of people contradict the principle of self-ownership. Yet at the same time, they cannot be limited by it, either, lest we fall into the fallacy that description equals prescription.