His complex moves toward ending slavery centered on the Emancipation Proclamation in 1863, using the Army to protect escaped slaves, encouraging the border states to outlaw slavery, and helping push through Congress the Thirteenth Amendment to the United States Constitution, which permanently outlawed slavery. Lincoln closely supervised the war effort, especially the selection of top generals, including his most successful general Ulysses S. Grant. He made the major decisions on Union war strategy. Lincoln's Navy set up a naval blockade that shut down the South's normal trade, helped take control of Kentucky and Tennessee, and gained control of the Southern river system using gunboats. Lincoln tried repeatedly to capture the Confederate capital at Richmond; each time a general failed, Lincoln substituted another, until finally Grant succeeded in 1865.