At that time, our country was divided by industrial might (North), which was expanding and manual labor (slavery in the South). And to be honest, our country would not have existed without it…not at that time.

Many of our forefathers knew that slavery needed to be addressed but many were involved in that trade, had more important issues to resolve like establishing a new nation and, in my opinion, just didn’t get around to it becuase of the seperation it involved in our country. This was corrected by Lincoln in the Emancipation Proclamation document and the 13th amendment but it did take a 100 years from the statement you are referring to. Something many, to include JQA, foresaw.