American liberalism, utilitarianism and the Declaration of Independence

A lot of people know the famous quote from the U.S. Declaration of Independence, written (principally) by Thomas Jefferson:

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.

Reading on reveals the left-wing philosophical underpinnings of the document and of the U.S. itself, however:

That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, --That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.

Which echoes this quote from British utilitarian philosopher Jeremy Bentham:

"it is the greatest happiness of the greatest number that is the measure of right and wrong".

If you look at the history of the American left right up to the present and regardless of which party was on the left at its time, you find this fundamental utilitarian philosophy, stated right there in the Declaration of Independence, in action:

"Government (founded) on such principles and organizing its powers in such form, as to (the people) shall seem most likely to effect their Safety and Happiness."

Every left-wing initiative in U.S. history, from good ideas like health care reform to abysmal blunders like Prohibition, would not have been possible without the basic American value that the people should organize the powers of government in the form that seems most likely to effect their safety and happiness. I think the idea forms the basis of nearly all left-wing thought, that ordinary people have both the ability and the right to try to improve upon circumstances and make the world happier and safer.

I'd be interested to see what others think about this.