Confederate leaders hoped that a victory in union territory would win support from:

Britain and France

This is considered as one of the most powerful countries during that time. These countries also do not want the United States to be a powerful country. Confederate leaders will have an effect in confederacy break away. However, during the emancipation proclamation. England and France both banned slavery and cannot support the Confederacy which sought to retain slavery.  It is quite clear that the Confederacy has little chance on their goal.