Just war theory is currently dominated by two positions. The standard view, reflecting current international law and formulated in the classic work of Michael Walzer, is that combatants both on the just and the unjust side have the same moral status (i.e. the same moral rights, duties, immunities and liabilities). According to this view, provided that jus in bello principles  are respected, all combatants have an equal right to fight, which is not affected by the justice of the cause pursued by their state.  This is because the most uncontroversial justification for the right to kill is our right to act in defence, and combatants retain this right, independently of the side for which they fight.
                This view has recently been challenged by neo-classical theorists like Cécile Fabre, Jeff McMahan and David Rodin.  The main objection raised by these critics is that the alleged “moral equality of combatants” relies on a fallacious idea, namely the presumed symmetry between parties who find themselves in the position of having to defend themselves against each other’s use of force. This symmetry, revisionists argue, cannot be correct. Thus, contrary to the traditional view, combatants are not morally permitted to take part in any war they are ordered to fight as long as they respect the requirements of jus in bello. Combatants must take responsibility for their actions and investigate whether the war they are required to fight is indeed just. Only if it is, do they acquire a right to kill.
                I argue that both the traditional and the neo-classical view capture important aspects of the correct way to think about the morality of war. Defenders of the neo-classical approach are right in pointing out that the justice of the cause plays a fundamental role in determining whether combatants can permissibly fight;  but they seem to lose sight of the fact that combatants act as members of a political body, and that this has important normative implications with respect to the rights and duties combatants have. These rights and duties also make a difference as to whether they can permissibly fight, but receive insufficient attention in the neo-classical account.