Keeping Kings in Check 69It is not suffi cient to fi ght in good faith, in the sincere belief that the law is on
one’s side. Th e law must actually be on one’s side, or the war is unjust. In legal
terminology, it would be said that there is strict liability on this point, mean-
ing simply that no allowance is made for subjective considerations such as
good faith. As a result, it was impossible in principle for a war to be just on
both sides. Wars were seen as inevitably just on one side and unjust on the
other, depending on which party had the law objectively on its side.
Th e fi fth and fi nal element of the schema was animus. Th is referred to the
subjective mental state of the combatant, though not to his opinion about
the justice of his cause. Instead, it was a requirement that a fi ghter in a just
war must do battle without personal animosity toward his foe. His battle
must be against wrongdoing as such, and not against the wrongdoers as in-
dividuals. Here is the refl ection, in just-war theory, of the Christian com-
mand to love one’s enemies. A just war should be seen as an enterprise in
correction and instruction, and not in vengeance or bloodlust. War waged
for greed or glory or for love of violence is unjust, even if the requisite iusta
causa is present.
A couple of general observations are in order about this body of thought.
One is that it was, for all practical purposes, entirely nonreligious in char-
acter, even if its chief expounders were theologians, and even though the
initial impetus for its development had been the challenge posed by Chris-
tian pacifi sm. Just-war doctrine was, of course, compatible with Christian-
ity (most obviously in the principle of animus). But the religious allegiance
of the contending parties played no part in the general structure of the
theory.
It should also be noted that the central concern of just- war doctrine was
the permissibility of resorting to force, not the methods by which the hostili-
ties were conducted. It should also be appreciated that just-war doctrine
concerned the entitlement to take off ensive action, in the sense of entitling
the just side to take the initiative by striking the fi rst blow and inaugurating
the hostilities. A just war must therefore be carefully distinguished from
self- defense in the strict and narrow sense, which is the fending off of an
actual attack. Th is narrow right of self- defense was of vital importance, to
be sure— but it was treated in medieval writing not as an example of a just
war by a sovereign, governed by the ius gentium, but instead as the exercise
of a general human right accorded by natural law.