Historian Andrew Preston says George Washington, Thomas Jefferson and Alexander Hamilton were not religious themselves but did see religion as a source of morality.
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March 15, 2012 Historian Andrew Preston says questions in an undergraduate class he was teaching at the start of the 2003 invasion of Iraq spurred the research for his new book, Sword of the Spirit, Shield of Faith. "Once I started looking for religion [in U.S. foreign policy], it was everywhere," he says.
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