In response to some off-line feedback asking for more information about our note that "any government law can ultimately be enforced only by violence," here are a few references with explication in more depth on this point:

• Enforcing the Law is Inherently Violent, Conor Friedersdorf, The Atlantic, June 27, 2016, citing Stephen L. Carter, William Nelson Cromwell Professor of Law at Yale Law School.
• State Monopoly on Violence, André Munro, Brittanica, noting: "State monopoly on violence, in political science and sociology, the concept that the state alone has the right to use or authorize the use of physical force... is widely regarded as a defining characteristic of the modern state."
• Enforcement of Private Property Rights in Primitive Societies: Law Without Government, Bruce L. Benson, 1989, Journal of Libertarian Studies, 9(1), 1-26, noting the well-accepted way to distinguish governmental from non-governmental social arrangements: "government induces cooperation through coercion, while privately arranged cooperation is achieved through persuasion." And also pointing out, by citing the below, that "any property rights system is ultimately backed by a threat of force and violence."
• Might Makes Rights, John Umbeck, 1981, Economic Inquity, 19(1), 38-59, where "violence is singled out as a major constraint."

It is also worth noting that this connection is explicit in the term "law enforcement" and the definition of "government" as a means by which organizational policies are enforced. Indeed, one may consider the thought experiment of disagreeing with a government versus disagreeing with a colleague to see which one ultimately leads to violence.

For a more fun read on this concept, Penn Jillette asks, "Would you use a gun to build a library or paint a picture?"