Union Secretary of the Navy Gideon Welles had long recognized Wilmington, North Carolina, as the key blockade runners’ haven in the war. He had tried to create an expedition to capture Wilmington’s prime defender, Fort Fisher. Welles, in conjunction with Rear Admiral Samuel P. Lee, conceived an attack where monitors would pass through Cape Fear’s Old Inlet and bombard Fort Fisher from the rear. A great idea: however, this mode of assault was impractical as the new Passaic-class monitors had too drafts too deep to enter the river. The Federals; nevertheless, did not forget about Cape Fear.
The Federals knew that Wilmington needed to be closed; yet, they also recognized the magnitude and extent of the Cape Fear defenses. Fort Fisher was key to General Robert E. Lee’s defense of Petersburg and Richmond. The food, weapons, ammunition, clothing, and medicines that Lee’s army relied upon all came from Wilmington, North Carolina. If this port city were to be captured, Lee would have to abandon his trenches outside of Petersburg.