The split between pluralists and nationalists was the split between those who wanted to combine with whites in a multiracial society and those who wanted to split from white society and live in complete segregation.
Both nationalists and pluralists believed in Black Power. They both believed that blacks should be aggressively proud of themselves as a race. The difference came in their attitudes towards whites. The pluralists envisioned a nation with the races getting along together while the nationalists felt that black culture would inevitably be overwhelmed in such a situation and that African Americans should, therefore, withdraw from white society as much as possible.