A question at rest in most nations, but not yet in the United States, is how one gains citizenship as of right. Clearly the right, in the United States as elsewhere, is gained at birth, as a birthright. The open question is: What are the circumstances of birth that give rise to citizenship? Case law is thin and scholarly commentary is divided. One claim is that birth on United States soil by itself confers citizenship. This metric is said to be historically determined, according to the (royalist) measure of "subject-ship" (jus soli per Calvin's Case) that preceded the American Revolution. The competing claim considers (as does most of the world) that a purely geographically determined citizenship is arbitrary, in that it requires no meaningful relation with the US as condition to citizenship. This second claim would dispel arbitrariness by positing a substantial relation with the US as an element of birthright citizenship, which relation is identified as one of "allegiance and consent". The history that underlies our supposed adoption of jus soli has its flaws. And as the second claim requires that birth be within a substantial relation with the United States, this claim better meets the conditions set by constitutional text, that of the Fourteenth Amendment as it provides citizenship to "All persons born in the United States, and subject to the jurisdiction thereof". As shown by ordinary heuristics, the "subject to the jurisdiction" condition entails a meaningful affiliation with the United States. This affiliation, though, is not well determined by allegiance and consent. These terms are not consistent with the leading case nor are they entirely consistent with baseline notions respecting the obligations of a sovereign to those who would be citizens. The appropriate baseline is better seen as one of "fairness", of fairness as reciprocity. Fairness as thus determined does not consist of a deontologically determined set of obligations and rights. Rather, fairness is more flexibly and generously built out of some better parts of human nature, parts essential to what recent scholarship identifies as the "civic minimum" in the liberal democratic state.