Why was Jefferson concerned about Napoleon Bonaparte’s plans?

He was concerned about napoleons plans because he was worried that France would shut down passage on the Mississippi River and farmers would not be able to get their crops to market in New Orleans.

Freeport Doctrine was Stephen Douglas's doctrine that, in spite of the Dred Scott decision, slavery could be excluded from territories of the United States by local legislation. Although propounded earlier and elsewhere, this solution of the apparent inconsistency between popular sovereignty and the Dred Scott decision.

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