(from Philip M. Katz, From Appomattox to Montmarte: Americans and the Paris Commune, Harvard UP, 1998).
'The Civil War, the Franco-Prussian War, and the Paris Commune each posed the question of republicanism in its starkest form: Shall "the people" be sovereign.' (89)
'But defining what "popular" (much less "republican") government proved elusive, as the bitter politics of Reconstruction showed. Reconstruction was a struggle to define what it meant to be a republic, and to decide who was fit to participate in such a polity.' (90)
Marx had followed the civil war in the US closely--his text on the Paris Commune is The Civil War in France.
(In the wake of the civil war, mistrust of popular government spread among Northerners: rejection of women's suffrage, acquiescence to Southern 'home rule,' ruins of 14th and 15th amendements, urban reforms limiting local autonomy, voting reforms limiting the franchise. The Commune became a way to 'focus and excuse the ideological shift away from popular government,' 92.)
For some, the Commune became an emblem of the failure of Reconstruction. The editor of the Nation, 'railed against the "Socialism in South Carolina" that came from allowing incompetent black men to govern and vote" (97). In his polemic againt reconstruction, the political incapacity in South Carolina was as bad as the Paris Commune. Attacks on the Communards were attacks on the political incapacity of the people. For Northerners, "neither Paris nor the South was ready for self-government" 100.
Related positions emphasized the parallel between Southern secessionists and the Commune, both rejecting centralized government. Some Southerners, not surprisingly, rejected the comparison and emphasized differences between themselves and the Commune, in particular, they (the South) were resisting revolution (the Union's attempt to control them) while the Communists were making a revolution. Other Southerners were happy to embrace the parallel, of "wholesome revolt against an oppressive centralized power" (107) -- the same position held by Northern Republican critics. Newspapers in Atlanta and Charleston expressed sympathy for the Communards. Still others associated the Parisian mob with the newly freed slaves.
(Weirdly, a former vice-president of the Confederacy, Alexander Stephens, who became a a member of Congress from Georgia after the war, identified himself as a Communist in 1880. For Stephens, to be a Communist meant to favor home rule, the sovereignty of the local government, 108-110. Stephens, of course, explicitly rejected the idea that communism entailed the abolition of private property.)