Supreme Commander is set in the distant future, and humanity has split into three competing factions. The United Earth Federation represents order and empire, the cybernetic Cybran fight for independence, while the alien-enlightened Aeon seek to liberate the universe. The single-player campaign is divided into three smaller campaigns, letting you battle from the perspective of each of the factions. Unlike those in most other RTS games, where all three campaigns would usually be tied together in a linear fashion to tell a bigger story, the campaigns in Supreme Commander all stand alone. Each faction fights for what it believes in, and hence, no side is really "evil." It's a nice touch, because that mentality captures the essence of war.