That's something we'll never know, will we - but you'll obsess over it none-the-less.<quoted text>What about all those great minds who were slaves? Maybe it has held the entire world back and only after slavery was abolished did we begin to achieve our greatest accomplishments. You know they used to saw off arms/legs during the Civil War, unthinkable with today's medicines and advances in science.
There were some great and influential people of color, you've chosen to marginalize them in favor of harping over what might have been. Look up "General Alex Dumas", he might sooth your soul.