But aren't you saying that the flag itself was a symbol of slavery?Essentially. That and segregation, once it was revived.
It wasn't designed to represent slavery. It was a flag of stars and stripes designed to represent the states consisting of the south, just as the north also had a flag of stars and stripes representing the states consisting of the north.
Both flags (north and south) were just variations of the stars and stripes that had been used in the past and continued to be used by American throughout history.