Related Rule
Practice Relating to Rule 7. The Principle of Distinction between Civilian Objects and Military Objectives
Section B. Attacks against military objectives
In 2008, in a joint cost benefit analysis of a possible introduction of a national moratorium on all cluster munitions, Denmark’s Ministry of Defence and Ministry of Foreign Affairs stated:
[The] provisions, which are outlined below, are generally recognized as being an expression of customary international law. …
The purpose of international humanitarian law is to protect the victims of war as much as possible. The central provision in this regard is API [1977 Additional Protocol] Article 48, which states that: “Parties to the conflict … shall direct their operations only against military objectives.” 
Denmark, Ministry of Defence and Ministry of Foreign Affairs, A Cost Benefit Analysis of a Possible Introduction of a National Danish Moratorium on All Cluster Munitions, 1 April 2008, p. 15.