There are so many examples of terrorist activity in the United States during the past 200 years choosing which ones to highlight is a difficult task. Which acts during the genocide of Native Americans that was the Indian Wars could be described as terrorism? Burning homes and killing noncombatants, women and children, was featured on both sides. I'll dedicate two postings to American terrorists and still no listing can be complete because terrorism is as American as apple pie.
John Brown, William Quantrill, and
The use of terrorism during an insurgency can rightly be said to have been invented in the mid-1800's in Kansas. In the years before the Civil War, Kansas was to determine through plebiscite whether it would be a slave or free state. Pro-slave Bushwackers and abolitionist Jayhawks pulled out their guns, intending to influence the vote by scaring their opponents out of the state. Murder, kidnapping, and arson abounded as both sides tried to kill the other. Whole families, including women and children, were killed because one member of the family was suspected of being an abolitionist (or pro-slaver). In 1856, when John Brown was just a mad preacher (see picture above) and not a national icon, he led a raid on three families along Pottawatomie Creek in Kansas. Under his leadership, five men were hacked to death with sabres because they were pro-slavery. William Quantrill rode on the other side of politics. Leading a gang of raiders that included the Jesse and Frank James and the Younger brothers, Quantrill killed over 150 men and burned 200 homes and businesses on his raid on Lawrence, Kansas in 1863.
John Mosby led a Confederate cavalry troop, the 43rd Virginia Cavalry. He and other Confederate Partisan Rangers developed many of the tactics still used by guerrillas around the world. They raided soft (unprotected) targets, worked in small units, and melted into the civilian population when challenged. To skedaddle was to scatter and run instead of fighting. The Union Army hated this cowardly tactic as much then as the U.S. Army hates it now in Iraq. Painting source.
Who masterminded the first terror attack upon New York City? Nope, not Bin Laden. It was in 1864 when Confederate Secretary of State Judah Benjamin sent eight agents into New York with dozens of fire bombs. They set fire to nineteen hotels and P. T. Barnum's museum. The goal was to incite a rebellion in the Northern city that most hated the Civil War. With all the optimism of Donald Rumsfeld at the gates of Baghdad, the plan predicted that the Confederate flag would be flying over the city by nightfall. The fires went off; the rebellion didn't.