Essay:Consent of the governed
Consent of the governed is the voluntary agreement of people to be ruled over by a government. This consent is typically not unanimous, or the point of government would be defeated. Depending on how one defines "government," it might even at that point cease to be a government. In a sense, consent of the governed amounts to a selling of oneself into slavery, because while the government claims to operate with the consent of the governed, if a person who consented to be governed is accused of having committed a crime, and then wishes to withdraw his consent to be judged and punished by that government, he will not be allowed to do so.
It is commonly argued that governments become tyrannical because their people reject freedom and want totalitarianism instead. Actually, it could simply be a snowball effect. As government exercises control over more and more aspects of people's lives, it becomes harder to express dissent. There are strong incentives to get in the government's good graces and disincentives to incurring the government's disfavor. What is more, the means of expressing dissent, i.e. the printing presses and other forms of private private property used to exercise free speech, tend to be among the pieces of capital equipment nationalized (whether outright or on a de facto basis by means of heavy taxation and regulation) by socialist governments. This in turn makes it even easier for government to exert more control, because the intellectuals have been bought off and the dissidents' voices have been stifled from objecting.
The U.S. Declaration of Independence and many U.S. state constitutions have clauses declaring that governments derive their just powers from the consent of the governed.