<span>a. to suppress dangerous revolutions in Europe.</span>
The blockade was supposed to prevent the South from getting resources and support from other countries who would support it such as those in Europe who were ready to recognize it as independent and help it if it meant that in the long run it would help them by weakening the Union.
Prohibition would have failed regardless of the atmosphere, because people like to drink alcohol. The permisive attitude of the times (mild compared to today) meant there was little social stigma attached to those who ignored prohibition. People finally came to realize that all they did was stregnthen the mob and lose tax revenues with Prohibition.
