MARY LOUISE KELLY, host:
The border between Mexico and Texas is easy to define. It's a river, the Rio Grande.
STEVE INSKEEP, host:
The rest of the U.S. Mexico border is not so obvious, straight lines drawn seemingly at random across mountains and deserts. Those straight lines cut through towns.
KELLY: They also cut through our imaginations and anxieties.
INSKEEP: We've built fences and security systems in an effort to control those lines. The historian Rachel St. John traced that border to its beginnings in the mid-1800s.
Ms. RACHEL ST. JOHN (Historian): The part of the border that I talk about, the western border, there's really no natural division. One of the things that's really interesting to me about the western border is that there's really no there there before the United States and Mexico sit down and decide that they're going to draw this line.
INSKEEP: Rachel St. John calls it "A Line In The Sand," the title of her new book. We reached her as part of our look back at 19th century events that still shape America today. The U.S. Mexico border is a product of the U.S. defeat of Mexico in a war in the 1840s. As the price of peace, the U.S. claimed vast stretches of Mexican land.
Ms. ST. JOHN: So when the U.S. and Mexican governments, their peace negotiators at the end of the Mexican American War sat down to create the border, they mostly picked a few, sort of geographically important points, a few points that they knew about, frankly, because neither government knew very much about this territory at all. And then they drew a series of straight lines between them.
INSKEEP: So it almost seems like chance to you that the border ended up being drawn where it is?
Ms. ST. JOHN: Um-hum.
INSKEEP: And there was even a discovery that once the border had been drawn that the United States didn't like where it had been drawn.
Ms. ST. JOHN: Well, it wasn't just that they didn't like where it was drawn, as that they messed up, basically. So what happened in the Peace Commission is that they wrote down a series of directions about where the border should be, so that it should start a marine league south of San Diego and run in a straight line to the Colorado River. And there's a long series of descriptive explanations. And then what they did is they attached a map the best map that they had at the time - of what this territory supposedly looked like. And they said, you should draw it from this point, that is not the city of Ciudad Juarez, from the position of Paso on the map.
Well, the problem is, when the boundary commissioners got into the field, it turns out that the map, it was in the wrong spot. And so the boundary commissioners, on the spot, had to make a decision; they decided to compromise and give a little bit more land to Mexico in one way and a little more to the United States in the other. And when this boundary came out, the U.S. Congress was not happy with it at all, and it's partly that discomfort about where the boundary line lay that led to the renegotiation of the boundary line in the Gadsden Treaty just five years later.
INSKEEP: Wasn't it something to do with a railroad? They wanted a railroad through the southern United States?
Ms. ST. JOHN: Yeah, there's a theory at the time that the best location for the railroad to go across the southern United States would be through southern New Mexico and through southern Arizona. But the railroad does not end up going through there for a very long time.
The other thing the U.S. did in the Treaty of Guadalupe Hidalgo, which ended the war initially, is that they promised to keep Indians, particularly Apaches, from raiding into Mexican territory, and they said they would pay for any damages basically caused by Indian raiding.
Well, it only took five years for the United States to realize that that was an impossible promise to keep. It's territory that's really controlled by Apaches at the time. And when the U.S. boundary commissioners and the Mexican boundary commissioners get out into the field, they realize Apaches are raiding heavily throughout northern Mexico and there is, at that time, very little the U.S. government can do to stop it. And one of the things they do in the Gadsden Treaty, then, is they back down on that provision they get Mexico to agree to basically let them off the hook for preventing raids.
INSKEEP: Which maybe saves the United States from paying compensation, but I supposed they still had this problem of thousands of Apaches who weren't particularly interested in where the United States and Mexico had drawn a line on a map.
Ms. ST. JOHN: Yeah, very little, although the Apaches, fairly quickly in the 1860s and 1870s, realized that they can also use this line to their advantage. The Apaches realized that if they are in the United States and they are being chased by U.S. troops, the best way to get away is simply to cross the border, because the U.S. troops can't cross into Mexican sovereign space. You know, there's this sort of cultural cliche of making a run for the border to escape law enforcement.
Ms. ST. JOHN: The Apaches are sort of the first people who learn how to do that and do it quite effectively.
INSKEEP: As you spent time along the western border, researching and learning and just looking around, how, if at all, did it affect the way that you understand the debates that we have the center around the U.S. Mexico border today?
Ms. ST. JOHN: I think, when people talk about the politics of the border today, they often refer to a sort of imagined historical time in which, particularly the U.S. government had control of the border. There's a lot of rhetoric of, we have lost control of the border. And studying the history of the border, I don't see a time when the United States ever had control. It's always a negotiation between governments trying to establish certain laws, people who want to evade those laws finding ways to do so, the government coming back, smugglers responding in turn. So there's always a sort of dance going along.
The other thing I think that really stood out to me is that, like most Americans, I think, I assumed going into this project that the border is primarily about immigration, and in some ways I think I imagined that the purpose of borders is to control the movement of people. And in the 19th century, that's just not the case at all.
INSKEEP: Although that's the major issue now, is the movement of people.
Ms. ST. JOHN: Exactly, and this is, I think, a 20th century phenomenon. It's something that's really changed on the border.
INSKEEP: One other thing, you point out, again and again, that when this border was drawn, on some level it didn't make sense. There had to be a border somewhere.
Ms. ST. JOHN: Um-hum.
INSKEEP: But the reason it was just in that spot is a little hard to explain. Now that it's been there for a good long time, does it make sense now?
Ms. ST. JOHN: It makes its own sense, and I think this is what initially got me so interested in the border is that, as I said, when the border is first created there is no there there. There's this somewhat arbitrary line drawn across a vast stretch of land. And then the border becomes this important space that draws people to it. People actually go to the border and establish towns, setting up ports of entry that monitor customs across the border. Then people decide to build businesses on the border in order to service those - the development of transporter trade.
INSKEEP: So the lesson is, in terms of borders, if you draw it, they will come.
Ms. ST. JOHN: I think so, I think so. And one of the things that's interesting about the border is that initially when the boundary commissioners were drawing this line, they all kept saying or many of them kept saying: This is a desert no one's ever going to settle here. There are actually parts of the border on the Baja California border where they were supposed to mark it more precisely and they made it a decision that look, no one's going to settle out here.
INSKEEP: They didn't bother.
Ms. ST. JOHN: Well, you know, it's 1850, it's hard to move around in the desert, it was hot you know, over, you know, 110 degrees and they literally say, Look we're not going to do a full survey of this line because no one's ever going to live out here. You know, I often think if those people could come back now, they'd be amazed to see places like Tijuana that they never could have imaged would develop.
INSKEEP: Rachel St. John is the author of "A Line In The Sand," a history of the western U.S. Mexico border. Thanks very much.
Ms. ST. JOHN: Thank you.
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INSKEEP: Tomorrow we'll continue our talks about how events in the 19th century shaped our world today, and our country especially. We'll ask how the great women's rights activist Elizabeth Cady Stanton turned against African Americans.
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