“We feel that our cause is just and holy; we protest solemnly in the face of mankind that we desire peace at any sacrifice save that of honour and independence; we ask no conquest, no aggrandizement, no concession of any kind from the States with which we were lately confederated; all we ask is to be let alone; that those who never held power over us shall not now attempt our subjugation by arms.”
No treasonous words or actions in that.
Not treasonous, ok. Firing on fort Sumter is an act of war against the United States.