In the south, you know when a storm is coming. The air is electric, a thin film of dew forms on your skin and the skies above transform into a mural of angry cloud gods. With giant sugar cane pots at my feet, looking out across the creek at the weather-worn outbuildings of those who once worked this land, I shuddered to think that this historic site was once destined to become a $700 million manufacturing plant. The Whitney Plantation nearly wasn’t, but for the intervention of a small group of preservationists, environmentalists, a wealthy white lawyer by the name of John Cummings and his head researcher, Ibrahima Seck, a Senegalese scholar. Their hard work…