Tony Dejak / AP

Birthright citizenship has been a bedrock principle of American civic society since Reconstruction. But it is steadily gaining opponents among the 2016 GOP contenders. Rick Santorum, Lindsey Graham, Rand Paul, and Bobby Jindal have called for an end to automatic citizenship for the children of undocumented immigrants; Chris Christie and Scott Walker have voiced their own doubts; and it’s a central element of Donald Trump’s new immigration plan.

The Fourteenth Amendment, for its part, is clear on the scope of birthright citizenship: “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.” Redefining the Citizenship Clause, either by legislation or by constitutional amendment, seems all but impossible today. “The only thing a politician could promise that would be harder would be, say, promising to build a giant, hundreds-of-miles-long wall and getting another country to pay for it,” The Washington Post’s Philip Bump drily notes. But like the proposed Great Wall of Mexico, feasibility may not be the point. It’s all about getting votes.

The last constitutional amendment used to resolve a political controversy was the Twenty-First Amendment in 1933, which reversed prohibition. Constitutional amendments since then have reformed either presidential election and succession procedures (the Twenty-second, Twenty-third, and Twenty-fifth) or elections themselves (the Twenty-fourth and Twenty- sixth). The Twenty-seventh and most-recently ratified amendment, which addresses congressional pay, lay dormant for over 200 years before a college student revived interest in it.

Indeed, since the defeat of the Equal Rights Amendment in 1982, no major social or political movement has seriously attempted to amend the Constitution to accomplish its goals. The anti-abortion movement, for example, generally focuses on limiting abortion’s scope through legislation and on supporting presidential candidates who will appoint Supreme Court justices to overturn Roe v. Wade. Opponents of capital punishment universally argue that the death penalty already violates the Eighth Amendment; advocating a separate constitutional amendment would undermine that argument. The gay-rights movement made the case that the Fourteenth Amendment’s Equal Protection Clause protects their rights, a position adopted by the U.S. Supreme Court in Obergefell v. Hodges in June.

But recent history shows the electoral value of proposing constitutional amendments. In 2003, the gay-rights movement scored two major legal victories: the Supreme Court struck down sodomy laws nationwide in Lawrence v. Texas and Massachusetts’s highest court legalized same-sex marriage under that state’s constitution. For conservatives at the time, the Supreme Court’s trajectory seemed obvious—and so did the solution. As the 2004 election loomed, the conservative National Review forecasted that the spectacle of same-sex marriage would hurt Democratic candidate John Kerry. At the time, the American electorate was still broadly hostile to marriage equality.

To hammer home this connection, the National Review pointed to the Federal Marriage Amendment. First proposed in 2002, the FMA would constitutionally define marriage as existing only between a man and a woman. A path to ratification would be arduous, the magazine argued, but the struggle would bring its own benefits. “Constitutional amendments must be approved by a two-thirds vote of Congress and three quarters of the state legislatures,” it eagerly noted. “That means every political candidate, from the state level up, will be asked to take a stand.” In essence, the 2004 election would become “a national referendum on gay marriage.”

If John Kerry is elected, gay marriage will surely be nationalized by the end of his term. A Bush defeat would take the wind out of the sails of the campaign for the Federal Marriage Amendment, assure liberal judges that no serious consequences will arise from nationalization, and bring more Goodridge-style liberals onto the courts. A Bush victory, on the other hand, would keep the FMA alive, would help signal the courts that they’ve gone too far, and would stop the proliferation of activist judges on our courts.

Evangelicals took credit when Bush trounced Kerry that fall, although some dispute their impact. But their perceived role went unrewarded when Congress didn’t pass the FMA after Bush’s reelection; Democrats then retook both houses in 2006, forestalling future attempts. As public acceptance of same-sex couples grew in the Obama years, most GOP candidates abandoned the amendment. (Texas senator and GOP presidential candidate Ted Cruz said last year that he still supports it, however.)

Republicans aren’t alone in using constitutional amendments to stir up their base, although they do it particularly effectively. After Al Gore was defeated in the 2000 presidential election despite winning the popular vote, some congressional Democrats proposed a constitutional amendment to abolish the Electoral College. Those efforts lost steam after Barack Obama trounced John McCain and Mitt Romney with significant margins of electoral votes. A similar movement emerged after the Supreme Court’s ruling in Citizens United v. FEC that struck down limits on corporate and union election spending. Vermont senator and Democratic presidential candidate Bernie Sanders proposed one of several amendments in 2011; Hillary Clinton said she would only appoint justices who pledged to overturn the ruling.

Could birthright citizenship still be undone? There’s a strain of legal thought that argues that a constitutional amendment wouldn’t be necessary. In 1985, Yale law professors Peter Schuck and Rogers Smith proposed that congressional legislation could clarify that the right does not extend to the children of undocumented immigrants. It’s not a completely heretical idea—Richard Posner, a prominent federal judge in the Seventh Circuit, endorsed it in 2010—but it’s not a mainstream one, either. When Congress considered similar legislation in 1995, Assistant Attorney General Walter Dellinger told members that a bill “that would deny citizenship to children born in the United States to certain classes of alien parents is unconstitutional on its face.” Although a constitutional amendment to achieve the same goal could not itself be unconstitutional, Dellinger also argued it “would flatly contradict the Nation’s constitutional history and constitutional traditions.”

Would the Supreme Court uphold a narrower view of birthright citizenship today? Curtailing the Citizenship Clause’s scope would be a seismic shift in constitutional law, beyond even Citizens United or Obergefell. The justices may also be reluctant to weaken a constitutional amendment explicitly designed to override a previous Supreme Court ruling—especially if that ruling was Dred Scott. But recent history shows that the easiest way to change the Constitution is not to amend it, but rather, to change the composition of the Court that interprets it. With three justices of the current Court turning 80 years old before the 2016 election, the next president might be able to do just that.

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