This thesis examines how the P3 states (France, the UK and USA) practically resolve tensions between their liberal preferences, practices of intervention, and the humanitarian solidarism of contemporary international society typified by R2P. It argues that where they behave as liberal vanguards, their practice threatens the sustainability of the solidarist international society typified by R2P. Using the cases of Côte d’Ivoire, Libya and Syria (2010-2012), it is argued that the P3 states either discursively advocated or attempted in practice liberal intervention which sought a change of regime or brought about actual regime change, contrary to the R2P normative framework which legitimates humanitarian intervention on a case-by case ...