 There is another sense in which the presence of a just cause is not sufficient to make war morally permissible. While making decisions about war, the ruler must consider not only whether his cause is just, but also whether its prosecution by the sword is beneficial to the realm's subjects. A war may pursue a just cause and yet involve injustice towards the subjects of the warring country if it manifestly harms the subjects' common good. In such cases, the ruler acts as tyrant; the subjects are merely treated as means to avenge wrongs done to him, while they themselves suffer serious loss (DDB 4.8).