"The name of American, which belongs to you in your national capacity, must always exalt the just pride of patriotism more than any appellation derived from local discriminations. With slight shades of difference, you have the same religion, manners, habits, and political principles." George Washington's farewell speech after his second term as president and after forming the nation and leading it to victory against the King. https://archive.ph/Q0Yea He said religion (which was protestant Christianity) was the necessary essence of all liberty and principles. "Of all the dispositions and habits which lead to political prosperity, religion and morality are indispensable supports. In vain would that man claim the tribute of patriotism who should labor to subvert these great pillars of human happiness--these firmest props of the duties of men and citizens. The mere politician, equally with the pious man, ought to respect and to cherish them. A volume could not trace all their connections with private and public felicity. Let it simply be asked, Where is the security for property, for reputation, for life, if the sense of religious obligation desert the oaths which are the instruments of investigation in courts of justice? And let us with caution indulge the supposition that morality can be maintained without religion. Whatever may be conceded to the influence of refined education on minds of peculiar structure, reason and experience both forbid us to expect that national morality can prevail in exclusion of religious principle." Same source above Furthermore almost all founders were protestant Christians. No other religion was as unstructured and conveyed to the individual the rights to all directly from god rather than a central authority. For example only one Catholic signed the declaration of independence. https://www.catholiccompany.com/getfed/did-any-catholics-sign-the-declaration-of-independence/