DAVID GREENE, HOST:
President Trump is heading to McAllen, Texas, today - again trying to convince the American public that a border wall is needed and that the government shutdown is worth it. The way President Trump has described this wall over time has changed quite a bit. NPR White House correspondent Tamara Keith has more.
TAMARA KEITH, BYLINE: Back in 2014, when the businessman Donald Trump was toying with the idea of running for president, he said he would build a border fence. That summer, a couple of his advisers, including Sam Nunberg, came up with the idea of calling it a wall as a way of signaling Trump would be an immigration hard-liner.
SAM NUNBERG: And what better way than to have his brand incorporated by Donald Trump saying, yeah, I'm going to build a wall. Nobody builds like Trump.
KEITH: Nunberg wants to be clear. Trump rejected plenty of their ideas, but he went all-in on the wall.
NUNBERG: It was fun. It was cool. It was novel.
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PRESIDENT DONALD TRUMP: I would build a great wall. And nobody builds walls better than me, believe me. And I'll build them very inexpensively.
KEITH: Trump officially launched his campaign in June 2015 with the wall as a centerpiece.
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TRUMP: (Chanting) Build that wall. Build that wall. Build that wall.
KEITH: That December, at a rally in Virginia, a little boy asked Trump for the specs on his wall.
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UNIDENTIFIED CHILD: What are the walls going to be made out of?
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TRUMP: That might be the best question I get today. I'll tell you what it's going to be made of. It's going to be made of hardened concrete. And it's going to be made out of rebar and steel.
KEITH: When he described his wall, he talked about concrete. He mocked those who said it would be hard or impractical, but it's worth noting that even very early on, he never said it would extend unbroken from sea to shining sea.
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TRUMP: Well, we have 2,000 miles. We actually need 1,000 - even less than that because we have a lot of natural barriers, right? Big, strong, wonderful natural barriers.
KEITH: After Trump became president, though, his description of the wall started to change. This was Trump on Fox News in November 2017.
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TRUMP: One of the things that's come up pretty strongly is we want to have vision through the wall because you want to see what's on the other side of the wall. You know, you think we're going to build a nice, simple concrete wall, but it's not that simple.
KEITH: That was a dose of reality meeting the president's concrete wall. For safety reasons, border agents want to be able to see what's on the other side, so the wall would actually be made of tall steel bollards, or posts, which, strictly speaking, is more like a fence than a wall. Still, Trump kept calling it a wall, kept leading chants at his rallies all through last year.
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UNIDENTIFIED CROWD: (Chanting) Build that wall. Build that wall. Build that wall.
KEITH: But now, with Democrats refusing to fund the president's wall, he's emphasizing the shift in building materials.
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TRUMP: You can never have border security unless you have a steel barrier, a concrete wall. You can call it whatever you want.
KEITH: Steel slats, steel barrier - it's not a concrete wall. But does that matter to the people who elected Trump to build a wall? Sam Nunberg, the early campaign adviser, says, no.
NUNBERG: What matters is that there's something built that has not been like anything that's built before, that is bigger, grander.
KEITH: Now, Nunberg doesn't claim to speak for all Trump voters, but he's looked at recent polling and focus groups.
NUNBERG: Trump supporters define success on the border as building the wall, and he has to build a wall or get a wall started.
KEITH: Trump's political future may well depend on it. Tamara Keith, NPR News.
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