"The right of a nation to kill a tyrant in case of necessity can no more be doubted than to hang a robber, or kill a flea"

John Adams draws a stark analogy between a tyrant and other threats to society, such as robbers and even fleas, to underscore the fundamental legitimacy of resistance against oppressive power. He frames the act of killing a tyrant not as a radical or extraordinary action but as one that is grounded in the same self-evident principles that justify defending oneself or one's community against a criminal or a pest. The mention of necessity is crucial: the right arises when circumstances compel desperate measures, implying that tyranny, like robbery or infestation, creates a scenario where the usual rules of deference are overridden by the demands of self-preservation and justice.

Adams appeals to an intuitive sense of justice, suggesting that no reasonable person questions the right to punish a thief threatening one’s life or property, or to eliminate a flea that poses a nuisance or harm. By grouping tyrants with such widely acknowledged threats, he strips away any sanctity or legitimacy that a ruler might claim simply by virtue of holding power. The comparison implies that authority is conditional upon justice and the consent of the governed. When a ruler becomes a tyrant, violating the rights and welfare of the people, he forfeits his claim to inviolability.

Furthermore, by equating the tyrant to lesser evils, Adams simplifies the moral calculus. The scale of the offense, robbery, infestation, tyranny, may differ, but the underlying principle remains the same: those who threaten the peace, liberty, or survival of individuals or communities may be rightfully opposed, even to the point of death. His words echo the broader revolutionary ethos that government exists to serve the people, not to enslave them. Tyrannicide, then, becomes not only a prerogative but a duty under dire circumstances, where all peaceful remedies are exhausted and direct action becomes the last defense of liberty.