Would you be surprised to learn that “God bless America” isn’t a standard closing for official speeches by U.S. presidents? In fact, the phrase wasn’t publicly used by a president until 1973 when Richard Nixon appealed to the American public in the face of the escalating Watergate scandal, according to the new book profiled by Huffington Post, The God Strategy: How Religion Became a Political Weapon in America.

Authors David Domke and Kevin Coe point out that despite Nixon adding “God bless America” to the closing of that particular address, Presidents Carter and Ford didn’t use the phrase. Ronald Reagan, who always signed off with “God Bless America,” catapulted the phrase into standard usage by our commanders-in chief.

Interestingly, from the inauguration of Reagan in 1981 to the Bush administration in 2008, 49 out of 129 major presidential addresses included “God bless America” compared to only one (Nixon’s) from 1933 through 1981. And last night, President Obama closed his 2014 State of the Union address by saying, “God bless you, and God bless the United States of America.”

According to Domke and Coe the phrase signals to voters that the commander-in-Chief is a God-fearing American. “It’s the verbal equivalent of donning an American flag lapel pin: few notice if you do it, but many notice if you don’t.”.

Such expressions are likely meaningful to the large swathe of the public who care about the religious commitment of their leaders. Roughly two-thirds (66 percent) of Americans say it is important for a candidate for public office to have strong religious beliefs. Additionally, 42 percent of Americans said ahead of the 2012 presidential election that it was very or somewhat important to their vote that a presidential candidate share their religious beliefs, while 58 percent said this was not too or not at all important.

How do you feel? Is it important for the president to say “God bless America” when publicly addressing the American people? Let us know in the comments.