During the War with Mexico, President James K. Polk authorized a battalion of men of the Church of Jesus Christ of Latter-day Saints. The Mormon Battalion became famous for having marched from Council Bluffs, Iowa, to San Diego, California. This is considered to be the longest march of foot soldiers in history. They were armed, but never had to fight in the war. What motivated President Polk to call up this battalion from what was then the out-cast Mormons camped out in Iowa territory? The War Letter answers that question. The War Letter is not about the Mormon Battalion but is the story of...