America was founded upon freedom of religion:
America as a Religious Refuge:
The Seventeenth Century
Many of the British North American colonies that eventually formed the United States of America were settled in the seventeenth century by men and women, who, in the face of European persecution, refused to compromise passionately held religious convictions and fled Europe. The New England colonies, New Jersey, Pennsylvania, and Maryland were conceived and established “as plantations of religion.” Some settlers who arrived in these areas came for secular motives—”to catch fish” as one New Englander put it—but the great majority left Europe to worship God in the way they believed to be correct. They enthusiastically supported the efforts of their leaders to create “a city on a hill” or a “holy experiment,” whose success would prove that God’s plan for his churches could be successfully realized in the American wilderness. Even colonies like Virginia, which were planned as commercial ventures, were led by entrepreneurs who considered themselves “militant Protestants” and who worked diligently to promote the prosperity of the church.
http://www.loc.gov/exhibits/religion/rel01.html
The freedom to practice a religion does NOT conflate to the United States being founded AS a religious nation. It’s not the Christian equivalent of the Islamic Iran. Anyone who thinks so doesn’t get it. If the founders intended this to BE a ‘religious” nation they would have enshrined a particular religion as the state religion in the constitution. They expressly prohibited any established religion. It’s today’s religious conservatives who are expressly trying to enshrine their religious beliefs into public policy. Which is exactly what the founders forbade in the constitution.