What did the Dred Scott decision help contribute to? the Missouri Compromise
abolitionist activities
the Civil War
Bleeding Kansas

We had many chances to avoid the Civil War, which is not to exclude the possibility of a (likely smaller and shorter) war restricted to the Deep South, either at that time or another time.

First, it was united American independence that set up the sectional conflict of equals. Britain was the greatest anti-slavery force of the time, and eliminating slavery needed to be a joint effort of Britain and the North, as suppression of the African slave trade had been since 1808. If both had been united with the South or both separate from the South, they would have approached anti-slavery in unison, pressing it only when they could apply the overwhelming force of both, making resistance impossible.

Explanation: