As the fear of spies and traitors spread through the North, political arrests became commonplace, even in states as far north as Maine. Anybody expressing any anti-war sentiment would be assumed to be a traitor and a secessionist, and arrests were carried out according to a guilty-until-proven-innocent policy. Martial Law was not confined to the slave states.
Chris Calton recounts the controversial history of the Civil War. This is the 23rd episode in the third season of Historical Controversies. You may support this podcast financially at Mises.org/SupportHC.