As for Fort Sumter, Congress had nothing to do with that.
That was U.S.property and Lincoln was in his right as President to send the fleet to protect it.
Not through South Carolina waters. The fort wasn't really in danger until Lincoln threatened the South Carolinians with an armed fleet. Mind you, I think the South was unwise to rise to the bait and attack the fort. They should have let Lincoln try to impose a blockade or collect the tariff on goods being imported on foreign ships, which would have been essentially international declarations of war. (Got to get that UN approval, don't ya know. LOL)
I'm out of here for a while.