Individualist anarchist and economist Murray Rothbard called No Treason "the greatest case for anarchist political philosophy ever written". In it, Spooner argues that the United States Constitution, as a legal contract, is invalid because individuals did not consent to it. In the context of the American Civil War, Spooner therefore supports the secession of the South, even though he was fiercely anti-slavery. Similarly, he argues that the secessionists did not commit treason, since they never signed the Constitution and therefore are not bound to it.
Spooner issued three pamphlets carrying the title of No Treason, numbered 1, II, and VI. Spooner, on publishing No. VI., wrote, "For reasons not necessary to be explained, the sixth is now published in advance of the third, fourth and fifth."