I’m saying Fort Sumpter was not located in the United States. It was located in another country called the Confederate States of America. They were warned to leave. Lincoln knew exactly what he was doing. He wouldn’t let it be evacuated. He got what he wanted. A war.
The Federal government built Sumter from the seafloor. It was to protect the waterways to prevent invasion. There was no reason to evacuate. If South Carolina wanted what the Federal government built from the seafloor, they should have brought it up in Congress before their attempted secession.