It encouraged Lincoln to issue the Emancipation Proclamation
Explanation:
The statement that best describes how the war on the Antitum affected President Lincoln's policy of war encouraged Lincoln to issue a declaration of emancipation.
On September 22, 1862, with the Confederate army's victory over the Confederates in the Battle of Antietam, President Abraham Lincoln allowed the Declaration of Independence.
This battle is also known as the Sharpsburg War of September 1862. It continued for a day, the South's attempt to invade the North. Historians regard this war as a bloody one-day war. The New Emancipation Proclamation declared freedom for all slaves in America.