[2] Mackaman has written and conducted interviews with historians challenging the New York Times' 1619 Project, first published on the World Socialist Web Site.
[10][non-primary source needed] He is active in public labor history, serving on the Anthracite Heritage Foundation[11] and helped secure a historical marker for the 1919 Baltimore Mine Tunnel disaster.
[15] The interviews, along with essays by Mackaman, David North, and other writers, were assembled in a book, The New York Times and Racialist Falsification of History.
[16] Mackaman ran for state legislature in Illinois in 2004 as a Socialist Equality Party candidate in the 103rd District covering the Champaign-Urbana area.
[20] Mackaman has written extensively for the World Socialist Web Site, especially on topics related to American history.