Read the orders sent by Secretary of the Navy Welles and Secretary of War Cameron. They give a different picture of what the expedition was ordered to do. General Scott had a different understanding of what was going on than members of the cabinet did. The fog of war.
I've read it. It says:
Should the authorities at Charleston, however, refuse to permit or attempt to prevent the vessel or vessels having supplies on board from entering the harbor, or from peaceably proceeding to Fort Sumter, you will protect the transports or boats of the expedition in the object of their mission-disposing of your force in such manner as to open the way for their ingress and afford, so far as practicable, security to the men and boats, and repelling by force, if necessary, all obstructions towards provisioning the fort and re-enforcing it
The Confederates saw it thusly: From Mr. Toombs, Secretary of State, CSA, April 24, 1861:
"[They] received the most positive assurances from Mr. Seward that the policy of his government was peace; that Fort Sumter would be evacuated immediately; that Fort Pickens would soon be abandoned; that no measure was contemplated “to change the existing status of things prejudicially to the Confederate States;” and that, if any change were resolved upon, due notice would be given to the Commissioners.Incredible as it may seem, it is nevertheless perfectly true that while the Government of the United States was thus addressing the Confederate States with words of conciliation and promises of peace, a large naval and military expedition was being fitted out by its order for the purpose of invading our soil and imposing on us an authority which we have forever repudiated, and which it was well known we would resist to the last extremity.
Having knowledge that a large fleet was expected hourly to arrive at Charleston harbor with orders to force an entrance and attempt to victual and reinforce the fortress, and that the troops of the Confederate States would be thus exposed to a double attack, General Beauregard had no alternative left but to dislodge the enemy and take possession of the fort, and thus command absolutely all the approaches to the port of Charleston, so that the entrance of a hostile fleet would be almost impossible.”
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. General Scott had a different understanding of what was going on than members of the cabinet did. The fog of war.
If you don't want people to mistake a resupply mission for a reinforcement mission, you should leave behind the several gunboats and armed riflemen.