And you disagree, why, exactly?
Your statement above is based on what happened, rather than what would have happened had they been left alone. Of course when you use warships to stop other people's ability to trade, it's going to seriously damage their economy, while those same warships interdicting their trade and directing it to your ports will boost your own economy.
But it misses the point. You can't claim their plan was flawed based on your side's deliberate interference with their plan.
This reminds me of the people saying Chris McDaniel was a bad candidate, while ignoring the fact that the Rino/Establishment deliberately torpedoed him.
DiogenesLamp: "Your statement above is based on what happened, rather than what would have happened had they been left alone."
But your claim is that "the South" produced 72% or 83% of all US exports and the facts of 1861 decisively disprove your claims.
In fact, in 1861 when "the South" was totally eliminated from US exports, they fell only 30% net.
Further, the Union's GDP quickly recovered and then nearly doubled by 1865, again demonstrating conclusively that "the South" was not as important as they had imagined.
Oh, you say, that's only because of the Union blockade and army invasions.
I take you to mean that: if Confederates had been allowed to force their wills on the United States, then the Confederate economy would have done much better and the Union economy worse.
Answer: maybe, but history doesn't provide real answers to such counter-factual speculations.