SCRATCH the surface of the Civil War, and you quickly find yourself studying black history. There's no escaping it. The Civil War is the central event of the American experience. African-Americans played a pivotal role in it. Their lot changed more as a consequence of the war than did that of any other participants.
Indeed, the recent popular interest in the Civil War, sent into orbit by last fall's PBS television series, gave white Americans a first-hand lesson in the substance of black history. For many viewers, the black role in the war came across as something more than a subject tacked onto a history lesson or tucked away in an African-American studies program.
During the conflagration, 180,000 black men fought on the side of the Union; four out of five draft-age black males left home, never to return; 4 million slaves were liberated. The South's political domination of both public affairs and the social order shifted irrevocably. Democratic free-labor capitalism replaced slave-labor plantation agriculture.
The PBS documentary offered an exhilarating and liberating understanding of a past that continues to influence the present. Any distinction between ``their'' history, meaning the South's or the North's or blacks' history, and ``our'' history, meaning America's, quickly blurs.
Like Ken Burns (producer of the PBS series), so too James M. McPherson, a Princeton University history professor and scholar of the Civil War, has been a prime mover in the resurgent interest in the war. McPherson, winner of the 1988 Pulitzer Prize for his massive single-volume account of the Civil War, ``Battle Cry of Freedom'' (Oxford University Press), has just added to his work a collection of short essays, ``Abraham Lincoln and the Second American Revolution'' (Oxford University Press, 173 pp., $17.95). This slim volume penetrates the meaning of the war and the role Abraham Lincoln played, one key part of which was the demise of that ``peculiar institution,'' slavery.