Childhood obesity and chronic disease rates continue to climb, but policy and programme responses are mainly limited to education and awareness activities. These encourage individuals to make responsible lifestyle choices. Regulation and environmental change have a minor role, as they involve more intrusive roles for government, invading traditionally private domains of nutrition and physical activity. But to address children's health needs, today's emphasis on self-management is inappropriate. Children, especially the very young, are dependent and vulnerable. I describe why the current public health strategies, with their political and moral foundations, remain ineffective. The foundations are based primarily upon the traditional liberal understanding of the public/private divide, while neglecting to recognize the legal obligations and implications of the United Nations Convention on the Rights of the Child and theories of justice and citizenship as they apply to children.