Throwing around "good" and "evil" in a discussion always makes me uncomfortable. Applying these simplistic labels really clouds the issue. Some assume that any action performed in support of 'good' is itself 'good'.
People and nations are not 'good' or 'evil'. They are self-interested. Actions performed by these people, in their own interests or on behalf of their nation, can be acceptable or intolerable, and can benefit or harm their own cause and the causes of their allies and opponents.
War is initiated primarily over control of resources. Gold, oil, access to holy lands, better farmland, water, terrorists being sheltered, whatever - someone else has something you want, and you take it by force. Everything else is justification. Some of these wars are just, many, perhaps most, are not.
When judgment is clouded by 'righteousness', horrible things can happen. Conversely, when positive goals are supported by moral certainty, terrific obstacles can be overcome. But I'd claim there is no such thing as 'innately good' or 'inherently evil' in this world, and I don't see evidence of it in Erfworld either.