In 1862, British and French textile workers were clamoring for Southern cotton as factories became increasingly idle. Lincoln had to come up with a strategy that would deter Britain and France from aiding the Confederacy while keeping the Border States in the Union.
The opportunity to test the water came on August 19, 1862 in the New York Tribune. Influential editor Horace Greeley wrote an open letter to Lincoln urging him to free the slaves to weaken the Confederacy. The editorial called, "The Prayer of Twenty Millions", resulted in one of Abraham Lincoln's most famous letters.
Lincoln states, "My paramount object in this struggle is to save the Union, & is not either to save or to destroy slavery." His response was a classic statement of Lincoln's constitutional responsibilities and prepared the public for the announcement of the Emancipation Proclamation on September 22, 1862.