Part I: The Declaration of Independence (1776) No document in American history can compare with the Declaration of Independence in the place that it holds in the minds and hearts of American citizens.
basic to American democracy: government is a compact among the people, and can be overthrown when it fails to fulfill its obligations; government exists to protect the rights and property of its citizens; every person accused of a crime is entitled to trial by a jury of peers; the state cannot search the homes of its citizens without a warrant; and taxes cannot be levied without the consent of the people.
From a constitutional point of view, the Declaration served several purposes. It enshrined the compact theory as the heart of the American philosophy of government, not only for the revolutionary generation but for succeeding ones as well.
Long after the particular grievances against George III have been forgotten, the belief that government exists to preserve the rights of the people, and can be dissolved if it fails to do so, remains a prime article of faith for Americans.
But even though the Declaration built upon generations of American and British experience, it went far beyond those ideas, and, in fact, as many modern writers have noted, it is a radical statement in its view of the purposes of government.
As nation-states began emerging in Europe in the late middle ages, the common assumption had been that governments existed to ensure order and protect the stability of society. But the Declaration of Independence, while not denying the need for order, asserts that the prime purpose of government is to protect the rights of the individual.
For the first time, it is the individual and not the society that is paramount, and the success of government is to be measured not by how well society is regulated, but by how free the individual is from government.
http://usinfo.state.gov/usa/infousa/facts/democrac/part1.htm