Easy, use the founding document that both the Declaration of Independence and the Bill of Rights were based on, the Virginia Declaration of Rights:
“That all men are by nature equally free and independent, and have certain inherent rights, of which, when they enter into a state of society, they cannot, by any compact, deprive or divest their posterity; namely, the enjoyment of life and liberty, with the means of acquiring and possessing property, and pursuing and obtaining happiness and safety.”
This proves that even among the Founders the concept stands valid without any creator. Where do you stand with the “key problem” gone?
XVI That religion, or the duty which we owe to our Creator and the manner of discharging it, can be directed by reason and conviction, not by force or violence; and therefore, all men are equally entitled to the free exercise of religion, according to the dictates of conscience; and that it is the mutual duty of all to practice Christian forbearance, love, and charity towards each other.
Note that little word "Christian" forbearance. Not "atheist autofellation" or "Randian neglect."
Cheers!