The Janus-Face of Ius Sanguinis: Protecting Migrant Children and Expanding Ethnic Nations Francesca Decimo Costica Dumbrava’s proposal for abandoning ius sanguinis is timely and bold. My intuition is to reject his suggestion that children’s citizenship might be disconnected from that of their parents, but to join his advocacy for a radical rethinking of the ius sanguinis principle with a view towards eliminating it once and for all. These are rather contrasting stances in relation to the same principle. Let us see if the apparent contradiction can be resolved. To begin, let us consider the element of Costica Dumbrava’s proposal that has elicited most attention and controversy among the respondents, but was picked up and expanded by Lois Harder, namely the assertion that granting citizenship at birth is unnecessary and, above all, that making children dependent on the legal status of their parents exposes them to a form of vulnerability. The idea of postponing the acquisition of citizenship until adulthood, taking into account birthplace and residence or possession of the appropriate attitudes and skills, derives from the classic opposition between ius sanguinis and ius soli according to which the former is considered ethnic and exclusive while the latter is considered civic and inclusive. Yet Rainer Bauböck’s comments on this point explain how, in the absence of parental transmission of citizenship to children, ius soli and ius domicilii can generate individual and familial conditions that are both legally paradoxical and morally unfair. I share the doubts and critiques raised by Rainer Bauböck, Scott Titshaw and Kristin Collins regarding the alleged emancipatory value of a citizenship system that disconnects children from their parents. Particularly, I consider any legal system that fails to specifically protect the relationship between parents and children to be highly risky. Indeed, who should children depend on if not their parents? Dumbrava’s proposal that children might instead be subject to, and protected by, a kind of international law faces the problem of subordinating the individual and familial reproductive spheres to institutional logics. © The Author(s) 2018 R. Bauböck (ed.), Debating Transformations of National Citizenship, IMISCOE Research Series, https://doi.org/10.1007/978-3-319-92719-0_22 113