STEVE GOLDSTEIN: President Trump told the TV program "Axios" on HBO he's looking to unilaterally end birthright citizenship via executive order. So-called "birthright" citizenship was granted with the ratification of the 14th Amendment after the Civil War. It reads "all persons born or naturalized in the U.S., and subject to the jurisdiction thereof, are citizens of the U.S. and of the state wherein they reside." The short sentence is somewhat deceptive. It is part of a larger hard won battle behind the scenes to create the longest amendment to the Constitution. And Arizonans are familiar with this fight — Senate Republicans here floated the idea of getting rid of birthright citizenship in 2011. Now that the 14th Amendment has again entered our current political dialogue, we're joined by Professor Eric Foner — a Pulitzer Prize winning historian and professor emeritus of history at Columbia University — to explain why this amendment continues to make waves. Professor Foner, thanks for being with us.

ERIC FONER: My pleasure. Yes.

GOLDSTEIN: So, what was the basic purpose of the amendment when it happened?

FONER: Well, the basic purpose was to put into the Constitution the victorious north's understanding of what the Civil War had accomplished — the end of slavery, the concept of equality before the law for all Americans and a national standard of citizenship that would apply all throughout the country. Before the Civil War, each state kind of decided who was going to be a citizen, and the rules varied enormously from state to state. Often it was very tied to race — many states refuse to recognize free black people as citizens of the state or the nation — and in fact the Supreme Court in the Dred Scott decision of 1857 explicitly said no black person even born here even free can be a citizen of the United States. So the 14th Amendment or that provision — the birthright citizenship provision — is meant to overturn Dred Scott and create a national standard. Anybody born in the United States is a citizen. It doesn't matter what your religion is, what your race is, what your national origin is, it doesn't matter what the legal status of your parents is. Your parents can be bank robbers, but that doesn't mean you're not a citizen if you are born in the United States.

LAUREN GILGER: So, these rights were put into an amendment specifically so they could not be repealed right? So how likely is this approach by the president by using an executive order here to uphold in court?

FONER: Well, you know, you've got five very conservative members of the U.S. Supreme Court today. I wouldn't predict what they would do. I mean, it's certainly flagrantly unconstitutional, and it also would violate longstanding precedent. I mean the Supreme Court ruled back in 1898 that the children of Chinese immigrants born in the U.S. are citizens even though at that time nobody from China could become a naturalized citizen. In other words the parents could not be citizens, but the children born in the United States were because of the plain language of the 14th Amendment. You know if we still have a Constitutional democracy; courts would have to overturn the president's executive order. The president, although he thinks he has a great deal of power, does not have the power to abrogate the Constitution. But as I say, I don't know what the five conservative members of the Supreme Court would do if it came up to them.

GOLDSTEIN: Professor, how did the argument pivot from the rights of former slaves to the issues of migrants from countries around the world settling in the U.S.? There are some similarities, but it does seem like more of a political pivot — is that what it is?

FONER: Well, I think the 14th Amendment became an issue lately because of undocumented immigration, which of course is a subject, you know, very well in Arizona, and which is whipped up right now very strenuously by the president. And, you know, I don't think there were that many people who deny that black people can be citizens, although President Trump, remember, he denied that Barack Obama was a citizen — which was a kind of an echo of the Dred Scott decision. But I think it's a question of what is the status of people born to those who are not citizens, or maybe even be undocumented immigrants. But the language is clear. You know, you can't just change the Constitution because you don't like the fact that — or abrogate the Constitution — because you don't like the way it actually is applicable at the moment.

GILGER: Tell us a little bit more about past challenges to this. I mentioned one — we mentioned one in the intro — about how the Arizona Senate Judiciary Committee here held hearings about ending birthright citizenship in the state back in 2011 when there was the SB 1070 debate going on — there was a lot of debate about this. Have we seen this happen over the years?

FONER: You know, no. I think that this provision of the 14th Amendment has not been very controversial until recently. There's very little jurisprudence about it — other than that Supreme Court decision of 1898 that I mentioned ... And, you know, I think it's been used lately as a political weapon. In 2010 the Tea Party, when they were first emerging at their rallies, they used to have signs you know repeal the 14th Amendment. I was teaching then and I would tell them, 'Well, what is it?' Why do they want to repeal the 14th Amendment? And that got students thinking about what is in the 14th Amendment, so it was a good teaching moment. But at least they said repeal the 14th Amendment, they didn't say just let the president eradicate the 14th Amendment — which would be a slightly different thing.

GOLDSTEIN: OK, Professor Foner we're going to stop there. Thank you. Professor Eric Foner is a Pulitzer Prize-winning historian, and professor emeritus at Columbia University.

FONER: OK, thank you. Bye, bye.

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