One of the main reasons why <span>some of the slaveholding states decided not to join the confederacy is because although they supported slavery, they were also patriotic, and felt that the Union needed to stay together no matter what the cost. </span>
It would be between increased population, a steady stream of agricultural production, and technological advancements. As for the most important one of those three; that would be agricultural production.
<span>struggles over the line of succession
is the write answer
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