There is a New South, not through protest against the Old, but because of new conditions, new adjustments and, if you please, new ideas and aspirations.

–Henry W. Grady,
1886

What is the main idea of this quotation?

The New South should reject any ideas that were part of the Old South.

The main idea of this quotation is that the New South should be characterized by new conditions, adjustments, ideas, and aspirations instead of protesting against the Old South. It implies that the region's progress should be driven by changes in its economic, social, and political conditions and the adoption of new ideas and values rather than opposition to the past.