Here is a starting reference, citing the following warnings from Samuel Adams and John Adams, two Founders of these United States of America, a father and a son who both served the People, as Presidents of our Nation: http://www.freerepublic.com/focus/chat/3306841/posts?page=6
" Immorality of every kind comes in like a torrent. It is in the interest of tyrants to reduce the people to ignorance and vice. For they cannot live in any country where virtue and knowledge prevail. The religion and public liberty of a people are intimately connected; their interests are interwoven, they cannot subsist separately; and therefore they rise and fall together. For this reason, it is always observable, that those who are combined to destroy the people's liberties, practice every art to poison their morals. How greatly then does it concern us, at all events, to put a stop to the progress of tyranny. It has advanced already by far too many strides. We are at this moment upon a precipice. The next step may be fatal to us." Samuel Adams, October 5, 1772
"Remember, democracy never lasts long. It soon wastes, exhausts, and murders itself. There never was a democracy yet that did not commit suicide." John Adams, 1814
In spite of all the anti-Bible and anti-Christ sentiment in the world today, if you were face to face with those presidents, they would vehemently urge you to make your peace with God's Word and God's ONLY Savior, Jesus Christ.