July 4 is America's birthday. We date our existence as people not from the Mayflower Compact in 1620 nor even (more logically) from 1787, the date that the Constitution, which still governs us, was born.
In the American faith, the people are prior to the Constitution, not formed by it, and July 4 celebrates the day we brought into being that new something: the Americans.
One of the persistent tropes of Americans is that we are a new nation. Certainly when compared to Europe, we have no very ancient history as a people -- no ruins of past iterations of our own civilization dot the landscape to remind us of any deep roots in the mists of prehistory. No mythical Romulus and Remus, suckled by wolves, form our creation myth. We know precisely from whom and how we came to be.
And yet America's is now almost certainly the oldest Constitution still operative on the face of the Earth. We may still be young, relatively speaking, as a people, but we are ancient of days as a polity. The endurance of America as one nation, under God, is a testament to the enduring power of what the men of 1776 bequeathed to us.
Our forefathers committed us as a nation to three great ideas that have stood the test of time:
The first is the idea of truth itself -- not only in the Declaration's insistence that we as a people hold certain moral truths to be self-evident, but the entire structure of the Declaration, its very reason for being, is testament to this faith in reason (and in the reasonableness of faith).
The second great American idea is grounded in the first: The rights of the people are prior to government. Each of us is "endowed by our Creator with certain unalienable rights, that among these are life, liberty and the pursuit of happiness." The Bill of Rights later adopted is thus not a gift of the government, but a statement of facts about human beings that the government is obligated to recognize. The Supreme Court's recent opinion recognizing that every American retains a right to keep and bear arms -- an individual right -- is only the latest in a long line of acknowledgements in which the Bill of Rights is so grounded. The whole case for human rights, and the liberties that stem from them, rests on the idea that government has no power to create rights, or to take them away, only to acknowledge or to abuse them.
We Americans are free (another gift from our Founders) to disbelieve in his existence, but not to change the facts of history: America exists because the Founders dared to rebel against the most powerful king on Earth, appealed "to the Supreme Judge of the world for the rectitude of our intentions," and "with a firm reliance on the protection of Divine Providence" mutually pledged "our lives, our fortunes and our sacred honor."