Answer: General Robert E. Lee, the commander of the Confederate Army of Northern Virginia, hoped that sending his troops to fight on Union soil would result in a show of strength in Maryland that might convince the state to join the Confederacy. However, this plan was foiled when Union forces discovered a copy of Lee’s orders and were able to intercept his army at Antietam Creek in Maryland on September 17, 1862. The resulting Battle of Antietam was the bloodiest single-day battle in American history, with over 22,000 casualties. Although the battle was technically a draw, it was considered a strategic victory for the Union because it forced Lee to retreat back into Virginia and prevented him from achieving his goal of winning a decisive victory on Union soil.
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