The chief historians who favored the Copperheads are Richard O. Curry and Frank L. Klement. Klement devoted most of his career to debunking the idea that the Copperheads represented a danger to the Union. Klement and Curry have downplayed the treasonable activities of the Copperheads, arguing the Copperheads were traditionalists who fiercely resisted modernization and wanted to return to the old ways. Klement argued in the 1950s that the Copperheads' activities, especially their supposed participation in treasonous anti-Union secret societies, were mostly false inventions by Republican propaganda machines designed to discredit the Democrats at election time. Curry sees Copperheads as poor traditionalists battling against the railroads, banks and modernization. In his standard history "Battle Cry of Freedom" (1988), James M. McPherson asserted Klement had taken "revision a bit too far. There was some real fire under that smokescreen of Republican propaganda".