Charter of the un says that they shouldn"t use force and that they should resolves their issues peacefully. O active: self defence - can"t use self-defence if it is below the threshold. Chapter vii 39-42: key parts that authorizes force by sc. This is only a breach of security, act of aggression if security council says it is, but if they don"t it doesn"t matter how violent the act is. 5 permanent (p5): us, china, russia, britain, france + 10 countries elected. O minimum of 9 have to say yes. O p5 countries must say yes, or abstain, even one p5 no is a veto. O if this happens, then finally it is considered to be breach of peace". Some kinds of war are considered a breach of peace under article 39. O un quotes lack of democracy as reasoning for involvement in haiti. O wide scale violations of humans rights reason to invade somalia.