Do not deny the reality – but it is ok to alter the SYMBOLISM to express more fully what you are memorializing.
What is becoming memorialized is that the issue of race is more important than what was done by those who exhibited heroic efforts at the scene of this tragedy. A more fitting memorial would be a very tall pillar shaped like the building. The surface would be covered with stone representations of the flyers put up by those looking for their innocent loved ones who died there. Standing next to it would be one stone figure crying representing the rest of us and another in uniform representing those who helped at the scene. It would represent Americans coming together at a time of need, not another representation of America being split apart by arguments about race.
