Under the principle of jus soli (right of the soil), almost all babies born on U.S. territory are granted automatic U.S. citizenship. This is enshrined in the 14th Amendment to the Constitution, which states that "all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens." In 2026, this remains the legal standard regardless of the parents' nationality or immigration status. The only rare exceptions involve children born to foreign diplomats who have "diplomatic immunity." Because these parents are not technically "subject to the jurisdiction" of the U.S. in the legal sense, their children do not receive birthright citizenship. For everyone else—including tourists, temporary workers, and undocumented immigrants—a birth certificate issued by a U.S. hospital serves as primary evidence of citizenship. This legal framework has been a cornerstone of American law for over 150 years, ensuring that any child starting life on American soil is considered a full member of the national community from their very first breath.