The Confederate Navy had a few warships yet could never confront the Union on the open sea. Although there were numerous sea battles between the North and the South, none were to involve more than two ships at a time. The Rebel navy was, non-existent.
The Confederate Navy would be forced to rely on their harassment of Union mercantile ships that were transporting supplies from the lower Northern states to the upper states.
Their method of destruction would come in the form of ironclads and slick seamanship. They knew all too well the consequences if they were to amass all of the ships of the Confederacy and stand against the Union navy. It would have been a turkey shoot.
The Union Navy had over 100 slopes and a few dozen cruisers and frigates. The South had a few ships that could, in a stretch, be fitted to resemble a warship. Naval superiority was never in question.
The Confederates relied on stealth and merchant ship piracy. The South had some friends though, overseas, supposedly, neutral, that would supply the Rebels with a few warships.
The French and the English supplied the bulk of the warships that the South had at its’ disposal. One in particular, The CSS “Florida”, was built in Liverpool in 1862. The Union had set up a blockade that was seemingly impervious to any shipping activities from Europe. The South got the CSS Florida through and after retrofitting guns and armor, the battle ship created havoc on Union vessels. Commercial or military, the ships supplied from Europe were spruced up by the Rebels, and were some of the best destroyers of the war. The combination of French and English sea-building skills, coupled with a great sense of ingenuity, helped make the Southern navy a minor force at sea.
The blockades that were set out to intercept any ships coming from the supposedly neutral countries and presented to the South were ineffective at best. The Atlantic Ocean is a huge expanse of territory, which was indefensible during the 19th century. Even today the surveillance that is required to monitor the Eastern seaboard takes a monumental-technological effort.
The CSS Florida, and others like it such as the CSS Alabama were successful in sinking many Union vessels. The numerical superiority of the Union Navy however was too much for the south to ever overcome and in the end the Confederacy could never win against the Union Navy.