 State consent does evidently play an important role in the formation of treaties. Treaties do not bind states that are not parties to them and have not consented to be so bound (Vienna Convention on the Law of Treaties, Article 34 [VCLT 1969]). But among treaties too, there are important caveats. The right to withdraw unilaterally from a treaty, which would grant states the full force of consent, does not, for example, apply to all treaties. The UN Charter is generally understood not to be open to unilateral withdrawal: member states of the UN can be expelled from the organization, but they cannot leave it voluntarily. Consent to it is thus irrevocable. States may be said to have consented to all of the rules that descend from UN membership when they first joined the UN, but the UN Charter is not a static body of legal obligations; it also governs processes through which rules of international law come into existence, and are interpreted and developed—processes which will take their course after the State’s initial consent to be bound by the Charter.