Secession was a peaceful act by the South. You're not free if you can't secede from an oppressive govt. In fact, that's what the original Revolution was about—secession. It's as American as apple pie.
“The power to declare war, including the power of judging the causes of war, is fully and exclusively vested in the legislature.” ~ James Madison, Father of the Constitution
“We do not believe in aggressive or preventive war. Such war is the weapon of dictators, not of free democratic countries like the United States.”~ Truman, Sept 1, 1950