As the nation debates Trent Lott's comments, it is important to understand what segregation really meant. First and foremost, this was not just a bad attitude but a vast set of laws designed to marginalize one group on the basis of skin color. Thus, racism was being enforced not by skinheads but by the police, by the courts and even by society itself; individuals who broke these statutes were condemned by the local community, just as we would do to lawbreakers today.

This legal web, furthermore, was amazingly complex. The South Carolina law covering textile factories barred workers of different races from working in the same room or using the same entrances, exits, stairways, pay windows or bathrooms. They could not stand at a window at the same time to comment on a new model car, and they could not use the same water fountains, drinking pails, dippers or cups. Oklahoma required separate phone booths for white and black patrons. North Carolina and Florida not only segregated schoolchildren but insisted that their schoolbooks be segregated -- in Florida they even had to be stored in separate warehouses -- so that no white boys or girls could ever be contaminated by even the dream of racial contact. States enforced segregation in prisons and in homes for orphans, the deaf, the poor and -- my favorite -- the blind. People who could not even see color had to be separated by race.

It was always clear, as well, that this was not just about physical separation but about keeping one group constantly ostracized, always humiliated. The Clarion-Ledger, Mississippi's leading paper, editorialized that, "If every negro" in the state "was a graduate of Harvard and had been elected class orator, he would not be as well fitted to exercise the rights of suffrage as the Anglo-Saxon farm laborer." In one small Delta community, the local postmaster made sure, before he boxed any mail for black residents, to mark out one word -- Mr., Miss or Mrs. -- so that no African American would ever be addressed by a title.

And to a vile extent, this system worked. Historians write about the heroes who stood up and challenged this travesty of the legal system, but they often forget the people who had to live with it every minute of every day and what it could do to them.

Lyman Johnson was a leader of the civil rights movement, but he recognized how segregation could affect a human being. In a book-length oral history memoir, he told about the time when he was in college at Virginia Union and he and a bunch of his buddies "went over to visit with some sorority girls in their rooming house." This was an old-fashioned courting party; as he noted: "We were all spruced up, and the girls were dolled up."

As the young people sat outside talking, a car came screaming around the corner of their dead-end street, with police in hot pursuit. The occupant was a bootlegger; his car couldn't handle the tight curve and plunged into an embankment. Officers went into the gully and began beating the lawbreaker, even though his legs and an arm were broken in the crash.

Hearing the screams, the house mother came out and beseeched the young men to intervene, pleading, "Don't let them treat that man like that. He's helpless. They'll kill him." But as Johnson noted, "we all sat still." The older woman then confronted the police, and paid a price in humiliation. When she asked them to stop attacking an injured man, they told her, "You tend to your own goddamn business. You better shut up and go back in your house, or you'll get some of this same medicine," and began calling her what Johnson referred to as "crude names."

As she came back on the porch, Johnson recalled, "She looked at us, but we couldn't look at her. There we were -- five healthy young black men. . . . Just a few minutes before we had been bragging with those girls making them think we were the saviors of civilization. Now we were cringing in fear." He explained, "In less than five minutes our manhood had been stripped from us. We felt completely impotent as the police threw that poor . . . man into the police car. . . . We were afraid of what would have happened to us if we had tried to interfere." He concluded, "We were like helpless aliens in our own country."

Running for president on a ticket of blind, absolute segregation was a nasty business in 1948; commenting favorably on that episode in 2002 should be unthinkable.

The writer is a professor of history at Chapman University in California.