Crucially important.
It prevented them from Importing and Exporting - in other words, exchanging their plentiful cotton for all the war supplies they couldn't manufacture for themselves, because they were agrarian not industrial.
Chat with our AI personalities
To starve them of the imported goods they needed, having no manufacturing industry, only agriculture.
skyrocketing food prices in the south
To prevent the Confederacy from exporting its plentiful cotton in exchange for war supplies.
It never did. The Union referred to the South as 'the rebel states'. However, by announcing a blockade of the Southern ports, the Union appeared to be giving the Confederacy the status of a separate nation.
Defeating the Confederacy, and restoring the integrity of the United States.