AP Explains: How US birthright citizenship emerged, endured

ALBUQUERQUE, N.M. (AP) — President Donald Trump said Tuesday he wants to end a constitutional right that automatically grants citizenship to any baby born in the United States. Trump, in an interview with "Axios on HBO," said his goal is halting guaranteed citizenship for babies of noncitizens and unauthorized immigrants.

U.S. citizenship through birth comes via the 14th Amendment , which was ratified after the Civil War to secure U.S. citizenship for newly freed black slaves. It later was used to guarantee citizenship to all babies born on U.S. soil after court challenges.

Here is a look at the Citizenship Clause and how citizens worked to be included in it throughout U.S. history:

THE 14TH AMENDMENT

In the aftermath of the Civil War, radical Republicans in Congress sought to push through a series of constitutional protections for newly emancipated black slaves. The 13th Amendment, which was ratified in December 1865, outlawed slavery. The 14th Amendment, ratified in July 1868, assured citizenship for all, including blacks. And the 15th Amendment, ratified in February 1870, awarded voting rights to black men, stating those rights should not be denied based on "race, color or previous condition of servitude."

"All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside," the 14th Amendment says. "No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States."

During a debate over the 14th Amendment, U.S. Sen. Edgar Cowan of Pennsylvania said birthright citizenship could result in "a flood of immigration of the Mongol race." He was referring to immigrants from Mongolia and China.

By extending citizenship to those born in the U.S., the amendment nullified the Supreme Court's 1857 decision in Dred Scott v. Sandford, which held that those descended from slaves could not be citizens.

Dred Scott and his wife Harriet were slaves who sued for their freedom after they were taken from the slave state of Missouri to the non-slave territories of Wisconsin and Illinois where slavery had been prohibited by the Missouri Compromise.

FIGHT FOR CITIZENSHIP Despite the Citizenship Clause and equal protections afforded under the 14th Amendment, Native Americans were consistently denied the benefits of U.S. birthright citizenship and it took decades for them to receive full citizenship, according to the nonpartisan National Constitution Center.