Emmanuel Dabney of Petersburg National Battlefield discusses the role of the U.S. Colored Troops in the Battle of the Crater during the siege of Petersburg. After weeks of tunneling, on July 30, 1864, Union forces blew up a mine underneath the Confederate lines to create a gap in their defenses. Mr. Dabney explains why the attack ultimately ended in a failure, and why the U.S. Colored Troops were unjustly blamed.