USS South America was used to block ports and waterways on states commonly referred to as what?
USS South America (1861):  She was acquired to be sunk as an obstruction in the channel leading to a Confederate port as part of the Union blockade on ports and waterways of the Confederate States of America. Confederate States of America: The Confederate States of America (CSA or C.S.), commonly referred to as the Confederacy, was an unrecognized country in North America that existed from 1861 to 1865.
the Confederacy