May 26, 2003, 9:00 PM --The most powerful accomplishment of tonight's segment of the PBS program, Ken Burns' "Congress," is that Mr. Burns managed to describe the period of official racism in America from just prior to the Civil War to the post-Reconstruction era, without once identifying a pro-slavery congressman or senator as a Democrat. When the Republicans outlawed slavery (which is exactly what actually happened), guess who walked out of the House and the Senate. Their party begins with the letter "D." Guess who after the Civil War worked to disembowell the black franchise. You have it. The same...