One of the main strategies used by the Union during the Civil War is known as the Anaconda Plan, which stopped the Southern states from importing and exporting goods.
During the Civil War period, the South was not industrialized at all. They did not have the same factory advantages the North did, so they heavily relied on outside forces to gear them up. The Union knew this, so they eventually came up with the Anaconda Plan. This plan was meant to constrict the South, like an anaconda would, and make it so they did not have access to ports.
The Union also planned to slowly surround the Southern states and eventually break them in two parts, so they would not be as powerful and would have trouble communicating with each other.