The State, by Franz Oppenheimer
A classic, and still under-appreciated. Murray Rothbard writes:
The great German sociologist Franz Oppenheimer (1864-1943), who wrote this magnificent little book called The State, put the case brilliantly.
In essence, he said, there are only two ways for men to acquire wealth. The first method is by producing a good or a service and voluntarily exchanging that good for the product of somebody else. This is the method of exchange, the method of the free market; it's creative and expands production; it is not a zero-sum game because production expands and both parties to the exchange benefit. Oppenheimer called this method the "economic means" for the acquisition of wealth.
The second method is seizing another person's property without his consent, i.e., by robbery, exploitation, looting. When you seize someone's property without his consent, then you are benefiting at his expense, at the expense of the producer; here is truly a zero-sum "game"—not much of a "game," by the way, from the point of view of the victim. Instead of expanding production, this method of robbery clearly hobbles and restricts production. So in addition to being immoral while peaceful exchange is moral, the method of robbery hobbles production because it is parasitic upon the effort of the producers.
With brilliant astuteness, Oppenheimer called this method of obtaining wealth "the political means." And then he went on to define the state, or government, as "the organization of the political means," i.e., the regularization, legitimation, and permanent establishment of the political means for the acquisition of wealth.
In other words, the state is organized theft, organized robbery, organized exploitation. And this essential nature of the state is highlighted by the fact that the state ever rests upon the crucial instrument of taxation.
This book is treasure trove of insight and steely analytics, with an introduction by Paul Gottfried. It is on the must-read list of every libertarian in every generation. $25 in the store.