Alexis de Tocqueville was a noted French political thinker and historian in the 1800's.
"I sought for the key to the greatness and genius of America in her harbors...; in her fertile fields and boundless forests; in her rich mines and vast world commerce; in her public school system and institutions of learning. I sought for it in her democratic Congress and in her matchless Constitution.
"Not until I went into the Churches of America and heard her pulpits flame with righteousness did I understand the secret of her genius and power. America is great because America is good, and if America ever ceases to be good, America will cease to be great."
See: Flood, Robert, The Rebirth of America (St Davids, PA: The Arthur S. DeMoss Foundation 1986) p. 39