2 The prohibition of the use of force
This chapter examines the prohibition of the use of force contained in Article 2(4) of the UN Charter, which provides that ‘All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations’. States and commentators generally agree that the prohibition is not only a treaty obligation but also customary law. However, there are disagreements between states on the interpretation and application of Article 2(4): does ‘the use of force’ include not only armed force but also economic coercion and, more recently, cyber attacks. Can humanitarian intervention ever be lawful? Is Responsibilty to Protect now a substitute for humanitarian intervention?