Well if you read any books about the devastation of slavery, you would understand the terrible effects it had on the continent. They stole and massacred millions of Africans, set the continent back hundreds of years, and set up bases for colonial then neo colonial exploitation that lasts all the way until today.
The largest Pan African movements were yes in the Caribbean but also in Africa! Kwame Nkrumah? Sankara?
You dont realize how letting an African country run with the movement will hurt it until its to late