Gary DeMar does a wonderful job of showing the true historical Christian roots of our nation without unduly sanitizing the founding fathers. This book does a number of things in the way of being a great primer to American history:
(1) Analyzes the role of government censorship, shows how it worked (in a bad way) throughout statist nations in history, and demonstrates the way it has happened and is continuing to happen in America today.
(2) Demonstrates from primary sources the original intent of the colonizing of America, the first charters, and the Christian great commission assumption of the early settlers up through the forming of the new nation.
(3) Handles the founding documents in their historical context, showing the true Christian nature of them - that is, even when the founding fathers were not all-together orthodox Christian, they still affirmed the necessity of the general principles of the Christian faith in order for the country to succeed.
(4) Addresses several misconceptions of what the founding fathers, founding documents, and other items do and do not say - in their historical context - over against what is taught in government-run public schools today in America.
It's a great read and a great reference.