“To say that the Union Navy won the Civil War,” writes McPherson, “would state the case much too strongly. But it is accurate to say that the war could not have been won without the contribution of the navy.”

With the end of the Civil War, the U.S. Navy’s sights quickly shifted away from an inward and coastal focus, and seapower in its blue-water sense became firmly implanted in the national psyche. The naval component of the Civil War had been a pivot point that assured fulfillment of a prediction made by John Paul Jones in 1778. At that time, Jones—not generally considered a seapower visionary—wrote to a friend who was pessimistic about the progress of the War of Independence and the state of the Continental Navy:

Our Marine [Navy] will rise as if by enchantment, and become within the memory of Persons now living, the wonder and envy of the World.

Jones might have been a bit off in his timing, but he was spot-on with the balance of his prediction. As the smoke cleared from the Civil War, the U.S. Navy’s sights were fixed on far horizons.

Joseph F. Callo is the author of John Paul Jones: America’s First Sea Warrior.