摘要： 美国的出生公民权宪法诉讼把国籍取得、移民治理、平等成员资格和司法救济集中到同一案件中。特朗普诉卡莎案从救济手段层面限制全国性禁令；特朗普诉芭芭拉案则在实体层面确认，在美国出生并通常受美国法律管辖的儿童，不因父母非法居留或临时居留而丧失宪法第十四修正案下的公民身份。通过梳理宪法公民权理论的自由主义、共和主义和保守主义三条路线，可以发现公民身份既是权利入口，也是公共资源、国家保护和公共负担之间的宪法性权利义务关系。在比较法上，无条件出生地主义具有特殊历史正当性，但如今已非主流；血统主义、有限出生地主义，仍属于当代国籍法主流模式。

Abstract: Constitutional litigation over birthright citizenship in the United States has brought together, within a single set of cases, questions concerning the acquisition of nationality, immigration governance, equal membership, and judicial remedies. Trump v. CASA limited nationwide injunctions at the remedial level, while Trump v. Barbara confirmed at the substantive level that children born in the United States and ordinarily subject to its jurisdiction do not lose their citizenship under the “Fourteenth Amendment” by reason of their parents’ unlawful or temporary presence. Examining the constitutional theories of citizenship—liberal, republican, and conservative—reveals that civic membership functions not only as an entry point to rights, but also as a constitutional relationship of rights and obligations linking public resources, state protection, and public burdens. From a comparative-law perspective, the American rule of unconditional jus soli possesses a distinctive historical justification, yet it is no longer the prevailing model today. The dominant contemporary approaches remain jus sanguinis and limited jus soli, which align with the mainstream modes of modern nationality law.

Key words: birthright citizenship, acquisition of nationality, genuine connection, equal civic community, public trust, ethics of responsibility