The Chief Medical Officer for England, Professor Sally Davies, and colleagues argue that it is time for a ‘fifth wave’ of public health, and influential organisations are seeking to advance this agenda. The fifth wave would progress from earlier shifts in public health, through structural, biomedical, clinical, and, most recently, social waves, towards a wave wherein the public’s health is recognised as a common good to be actively promoted through participation of the public as a whole. Davies and colleagues categorise this fifth wave as cultural, emphasising the cultivation through institutional, social, and physical environments of shared beliefs, values, and behaviours in which pro-health attitudes—individually and at a societal level—are normalised. They advocate for their agenda within a political context that has undermined the highest attainable standards of health through an individualism that defies what is shown by epidemiological studies on the social determinants of health. Focusing on the practical case study of the ‘tobacco endgame’, my paper examines the fifth wave agenda through a public health ethics and law perspective. It critically explores the viability of political justifications for a public health policy strategy that works through a long-game, cross-sector approach of progressive achievement of change. This requires a study both of the justification of the goal that is aimed at and, crucially, the means of achieving it. Given the dominant political context, it is unsurprising that efforts are made to find ‘neutral’ normative framings, such as those promoted by reference to ‘libertarian paternalism’. It is argued, however, that these are inherently deficient as coherent sources of legitimacy: there may be strategic or ‘real politics’ reasons to frame justifications in this way, but the philosophical foundations of efforts to promote the public’s health require a greater—and more contestable—critical depth.