War at sea can be fought using either "sea power" per Mahan or "guerre de course"-commerce raiding. Sea power in Mahan's terms referred to the power of the navy and "maritime economic power" (Pike). Mahan felt that control of the seas and maritime commerce were vital for a nation's war effort, arguing that the use of "large concentrated battle fleets" was a tactic for wresting control of the seas and closing the enemy out of it (Pike). Sea denial, or "commerce-destroying," was "a means for harrying and tiring an enemy" and could prevent the loss of a war, but commerce raiding by itself is not a strategy that wins a war, nor does it serve to deter the enemy very effectively (Pike). Pike cites naval strategists that contend that it takes different types of ships to win control of the seas than it does to exercise day-to-day control on an ongoing basis, pointing out the German submarine force comprised of U-boats exercised economic warfare against the Allied forces very effectively.
Of the two activities-actions to defeat the enemy battle fleet and commerce raiding-actions to defeat the enemy battle fleet best describes the use of sea power in war. While commerce raiding can distract and harass the enemy, it does not win the war, but actions to defeat the battle fleet can produce a victory by sinking key ships, closing off a path of escape, or simply eliminating so many of the enemy's forces that it cannot fight back.
Pike, John. "Commerce Raiding." GlobalSecurity.org. ...