In God We Trust is our national motto. How did the War of 1812; the Civil War; and the Cold War combine to give us this motto?
How did America adopt the motto "In God We Trust?" In the War of 1812, Francis Scott Key wrote "The Star Spangled Banner" while watching the British bombardment in Baltimore harbor. In the 4th stanza, he wrote "And this be our motto: 'In God is our Trust.'"
Then in the Civil War, Congress decided and passed a law that the motto "In God We Trust" would be put on our nation's coins. And from that day until today, "In God We Trust" has appeared on some or all of our nation's coins.
The official national motto, however, remained "E Pluribus Unum" -- from many one -- until 1956. In 1956, our country was at an extremely tense time in the Cold War with Russia, which was an atheistic state. America wanted to make a clear distinction with Communist Russia, and so the Congress passed -- and Pres. Eisenhower signed -- a law stating clearly that our official national motto would henceforth be "In God We Trust."
Since 2000, the Senate has reaffirmed "In God We Trust" as our national motto; the House of Representatives has voted overwhelmingly in favor of the motto; and a Gallup poll found 90% of Americans approved. So that is how we stand today with "In God We Trust" as our national motto.