The “subject to the jurisdiction” clause could be the loophole needed but it would need a sympathetic SCOTUS to get through

The immigration debate is reviving the explosive idea of denying citizenship to children born on U.S. soil if their parents are in the country illegally.

A U.S. senator and a state lawmaker in Arizona, both central players in the battle over immigration law, separately proposed this week that “birthright” citizenship be denied to the children of illegal immigrants. They said the change would help stem the flood of illegal border crossings.

“People come here to have babies. They come here to drop a child,” Sen. Lindsey Graham (R., S.C.) said Wednesday night on Fox News. “That shouldn’t be the case. That attracts people here for all the wrong reasons.” Mr. Graham is a onetime partner with Democrats in crafting a proposed overhaul of immigration laws.

Immigration-rights activists say citizenship isn’t a significant driver of illegal immigration, because a child has to reach age 21 to petition for permanent legal residency for his or her parents.

Such calls to change what has been a bedrock feature of the immigration system are sure to set off contentious debate. “It’s an extreme position, and Sen. Graham knows this,” said Angela Kelley of the left-leaning Center for American Progress. “He’s not one to tamper with the Constitution, so I’m surprised he would even suggest this.”

In Arizona, Republican state Sen. Russell Pearce, the architect of the immigration law that drew a legal challenge from the Obama administration, said he wanted to deny U.S. citizenship to children born in his state to illegal immigrants.

At issue is the 14th Amendment to the U.S. Constitution, enacted in 1868 to ensure that states not deny former slaves the full rights of citizenship. It states, “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.”

Mr. Graham, speaking on Fox, suggested that changing birthright-citizenship rules would require a constitutional amendment. “We should change our Constitution and say if you come here illegally and have a child, that child’s not automatically a citizen,” he said.

He said he was considering introducing such an amendment. A spokesman said Thursday that Mr. Graham was just discussing the idea and hadn’t made any decisions about whether to move ahead.

Mr. Pearce, like some other proponents of the change, argued that the amendment as written doesn’t apply to illegal immigrants. Because illegal immigrants aren’t “subject to the jurisdiction” of the U.S., as the amendment requires, they fall outside its protection, these people argue. A group of House lawmakers made a similar argument when they tried to pass legislation changing the birthright principle in 2005.

“When it was ratified in 1868, the amendment had to do with African-Americans; it had nothing to do with aliens,” Mr. Pearce said. “It’s got to be fixed.”

Given the controversial nature of this proposal, successfully amending the Constitution would be considered a long shot. It requires a vote of two-thirds of the House and of the Senate, and must be ratified by three-fourths of state legislators.

A change in state law redefining who is a citizen would likely draw a legal challenge, as did Arizona’s effort to change state immigration law.

Under Mr. Pearce’s proposal, Arizona would refuse to issue a birth certificate to any child unless at least one parent could prove legal presence in the U.S. “The 14th Amendment has been hijacked and abused,” Mr. Pearce said. “We incentivize people to break our laws.”

The U.S. is home to about 11 million illegal immigrants. There are nearly four million whose children are U.S. citizens, according to a 2009 report by the Pew Hispanic Center, a nonpartisan research group in Washington.

Dan Stein, president of the Federation for American Immigration Reform, which calls for cracking down on all immigration to the U.S., said that citizenship as a birthright isn’t automatic in many countries in the West.

“We should not allow language from 1868 to enslave our thinking…in the 21st century,” Mr. Stein said.

Mr. Pearce was sponsor of SB1070, the law that required police to check the immigration station of anyone they stop if they suspect unlawful presence. On Wednesday, a federal judge blocked that provision and others, pending further legal review. Arizona Gov. Jan Brewer, who signed the bill into law, has promised to appeal.