How Birthright Citizenship shapes America’s population — the numbers tell all

The U.S. Supreme Court recently held a hearing about the automatic citizenship of children born in the United States—-attended by the POTUS Donald Trump. Known as Trump VS Barabara, the hearing was to take a call on the legality of the President's power to limit birthright citizenship. Trump signed the order soon after taking office in January 2025, and he personally watched the hearing — which is unusual for a sitting president.

The court is expected to give its final decision sometime this summer. This is the second time the U.S. Supreme Court has reviewed Trump’s citizenship order. On June 27, 2025, the justices voted 6-3 to partly allow the order to move forward by stopping some lower-court blocks, as stated by USA Today.

The Supreme Court said the district courts may have gone beyond their power when they blocked the order. However, the court did NOT decide if Trump’s order is constitutional. During earlier arguments on May 15, none of the justices clearly supported the claim that the order matches the 14th Amendment.

Birthright citizenship rules explained

Since 1868, birthright citizenship means anyone born in the United States automatically becomes a citizen. This rule applies to children of citizens, legal immigrants, and undocumented immigrants. Changing this rule could affect a large part of America’s population. More than 25 million foreign-born residents are naturalized U.S. citizens, as per the 2024 U.S. Census Bureau data. The Migration Policy Institute and Penn State Population Research Institute also estimated about a quarter of a million new- born children will be rendered without citizenship each year.

It could also lead to the increase in the number of unauthorized migrants—-by about 2.7 million by 2045. In 2022, about 4.4 million under 18 US - born children had at least one undocumented immigrant, Pew Research Center said. As noted by USA Today. The number of unauthorized immigrants peaked at 12.2 million in 2007, according to Pew estimates.

Where foreign-born residents live

In 2022, nearly one-quarter of foreign-born people in the U.S. lived in California.Foreign-born residents made up more than 20% of populations in New Jersey, New York, California, and Florida, as stated by USA Today.

Foreign-born residents include naturalized citizens, permanent residents, students, refugees, and undocumented migrants. Almost every state saw an increase in foreign-born population from 2010 to 2022. Delaware, North Dakota, South Dakota, and West Virginia had the biggest increases — more than 40%.

Immigration trends and global comparison

The foreign-born share of the U.S. population has grown over decades. In 1970, only 4.7% of people in the U.S. were born outside the country. By 2022, that number rose to 13.9%. More than half of foreign-born residents came from Latin American countries. Nearly one-third of foreign-born residents came from Asian countries.

The Council on Foreign Relations explains that naturalization is when a non-citizen applies for citizenship after meeting rules like passing a civics test and basic English. According to Pew Research, 32 other countries — mostly in the Western Hemisphere — also allow birthright citizenship similar to the United States, as cited by USA Today. Birthright citizenship affects millions of people and could change future population numbers depending on the Supreme Court’s decision.

FAQs

Q1. What is birthright citizenship in the United States?

Birthright citizenship means most children born in the U.S. automatically become citizens, based on the 14th Amendment.

Q2. How could ending birthright citizenship affect the U.S. population?

Experts say it could increase the number of non-citizens and leave many children born in the U.S. without citizenship.