The ceremony for the signing of the Atlantic Charter is a good example. A reading from Joshua was given, "Be strong and of a good courage; be not afraid...for the Lord thy God is with thee whithersoever thou goest." Meacham says that Churchill wept. Three hymns were sung by a mix of American and British sailors: "Onward Christian Soldiers, Eternal Father, Strong to Save and the beginning of Psalm 90."
O God, our help in ages past,
Our hope for years to come,
Be Thou our guide while troubles last,
And our eternal home.
The author, continues to conjecture that Americans were wary of this strongly Anglican service. What if you're not Christian? Americans prefer an ecumenical service (ministers of different faiths) but the theme of the ceremony was universally accepted: liberty, justice, and democracy.
Franklin played the part of a national pastor. I think he looks the part. Can't you picture him as a rabbi, minister, or priest? On D-Day, June 6, 1944, the President led the country in prayer. He asked that our military operation against the Nazis be blessed with success.
What I've just quoted is a good example of the book. The theme is that religion shapes politics. And at this particular time before the election, the book is comforting. It's "good news" that religion shapes politics, yet doesn't control it. Right from America's founding, our nation has struggled with faith and government. It proves that God is in charge.