One way the Anaconda Plan and naval blockade harmed the Confederacy was by

Blocking the southern ports and controlling the Mississippi River would isolate the confederation from the rest of the territory.

Explanation:

The anaconda plan can be developed by the general of the United States Army Winfield Scott, during the civil war that took place between the confederation and the union. The anaconda plan aimed to establish a blockade of the confederation that would prevent them from transporting their troops and eliminate the export of cotton and other products to the countries of Europe, as well as preventing the import of supplies for them, through the posts south and the Mississippi River.

The anaconda plan was considered impossible to carry out due to the territorial extension of the blockade, but it was possible to achieve it during a hard time of the war, which had as a result affecting the economy of the Confederates and with the use of other military strategies the union was able to win the war.

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