The Global Army wasn't at war, at least politically. Humankind had many interests across the universe, but it didn't have a proper enemy since the Nak already occupied that spot.
Still, battlefields existed on different planets. Most of them were environments devoid of other intelligent species but with Tainted animals and monsters that the Global Army had to suppress to continue harnessing eventual resources. However, others involved complicated interests and aliens that the humans wanted to help to obtain benefits.
Ecoruta was one of those environments. The planet featured two intelligent species constantly at war, and the humans had decided to side with one of them to get a share of the natural resources. Apparently, that world was like Onia since it contained one of the core metals used in the creation of vehicles meant for space.