SCOTT SIMON, HOST:

The NPR News team traveled more than 2400 miles along the Mexican border from the Gulf of Mexico to the Pacific. Their route led through a zone that's under intense surveillance. NPR's Steve Inskeep got a chance to watch those who watch the border.

STEVE INSKEEP: You see Border Patrol vehicles all over the U.S. side of the borderland. Their green and white SUVs are being filled up at gas stations or parked by border fence. But the agents inside can't be everywhere, so they use technology like cameras and sensors that monitor a stretch of the Rio Grande near Laredo, Texas.

BARINE SALLAS U.S. CUSTOMS AND BORDER PROTECTION: Well, welcome to our communications room.

INSKEEP: Berine Sallas(ph) of the Border Patrol showed us in. About half a dozen people monitored calls from the field.

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INSKEEP: The room had no windows, just a giant wall of screens. The Border Patrol, officially, it's part of U.S. Customs and Border Protection, has mounted cameras high in steel poles overlooking the border.

PROTECTION: We have 24 sites. On each site we have two cameras. The cameras have nighttime and daytime capabilities. If you can see on that screen, that's approximately a mile and a half.

INSKEEP: And we're looking right down the Rio Grande?

PROTECTION: Yes, we're looking at down river of the Rio Grande.

INSKEEP: One agent was using a joystick to move a camera, studying semi trailers in a riverside parking lot. A whiteboard on the wall was covered with emergency numbers to call, including a phone number marked unmanned drone. The man in charge of this south Texas sector tries to marry new technology with old. Commander Robert Harris keeps a saddle in his office.

COMMANDER THOMAS HARRIS: We still do have horses and I would argue that we have some of the best trackers in the country.

INSKEEP: They're trained to follow footprints in the wilderness along the border. That's labor-intensive work, but the Border Patrol nearly doubled its manpower in recent years to more than 21,000.

HARRIS: No, we don't have 100 percent visibility on the border, but I have a much higher degree of confidence in terms of our strategy that if somebody chooses to enter through our area of responsibility, we have a higher than average chance of arresting that individual.

INSKEEP: But the Border Patrol is under intense pressure in a series of incidents in recent years, including one here in Laredo. Border Patrol agents shot and killed unarmed Mexicans. In some cases, the Mexicans were said to be throwing rocks. This month, the Border Patrol reminded agents to avoid, quote, "unnecessary risk to themselves or others." But it resisted calls for bigger change, saying agents had been pelted with rocks hundreds of times per year.

HARRIS: We're not in a situation to lose fights. You know, if our agents are assaulted, I want them to prevail.

INSKEEP: The Border Patrol is also criticized for not doing enough, as we heard when we continued our road trip. Outside Eagle Pass, Texas, we arrived at the home of a rancher whose property lines the border.

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DOB CUNNINGHAM: We have coffee if y'all want a cup of coffee?

INSKEEP: I would be delighted to have coffee, thank you.

And after the coffee, Dob Cunningham took us for a jeep ride on his property.

CUNNINGHAM: Do hang on.

INSKEEP: Cunningham drove, his wife Kay was beside him rancher.

KAY CUNNINGHAM: This gray bush that you see, when it blooms it's a mauv-y pink color and it's just beautiful. The whole ranch is covered with it.

INSKEEP: The people in back included Larry Johnson, Dob's friend, and a former sheriff. Dob Cunningham sees threats concealed in this land.

CUNNINGHAM: About a year ago they came over here to my shop and took all the tools, stole all the tools and a (unintelligible) just like that.

INSKEEP: By they he means thieves crossing the border. Cunningham is 79. Decades ago he was a Border Patrol agent and later ran the U.S. Port of Entry at Eagle Pass. These days he's developed a love/hate relationship with the Border Patrol. And to show us why, he was driving us toward a bluff overlooking the Rio Grande.

And I guess that must be the river below us in this valley?

CUNNINGHAM: And Mexico on the other side.

CUNNINGHAM: And that's Mexico.

INSKEEP: Cunningham prepared to stop just sort of where the bluff plunged down toward the river.

CUNNINGHAM: If I holler bail out, jump out 'cause sometimes these brakes don't work.

INSKEEP: OK. We're about to go downhill.

CUNNINGHAM: Real fast.

INSKEEP: We stopped in time at the foot of a giant steel pole.

CUNNINGHAM: All right.

INSKEEP: It held two of those border patrol cameras aimed up and down the river. Cunningham said the wire to one camera was cut. He says his property is periodically flooded with thieves, marijuana smugglers or migrants. When he can, Cunningham rounds them up and turns them in.

CUNNINGHAM: It's not in us to steal a penny or to turn a blind eye. It's just not in us. It's not our way.

INSKEEP: Or just ignore it, let it happen.

CUNNINGHAM: It's not in our way. It's not in us. The Border Patrol gets after me for calling in and catching stuff. Not all of them but some of them.

INSKEEP: Oh, the border patrol maybe would rather you do a little less?

CUNNINGHAM: Oh, yeah. They'd rather me, you know, turn a blind eye.

LARRY JOHNSON: Well, it was a week ago today, remember?

INSKEEP: His friend Larry Johnson recalled the day they found three people on the road they suspected of crossing the border illegally and picked them up. Kay Cunningham recalls another incident right here on the ranch.

CUNNINGHAM: I call it the night of the big shootout.

INSKEEP: Dob spotted something just at dusk and took his gun to have a look.

CUNNINGHAM: I heard bam, bam, bam, bam, bam. Then I thought, oh, my God.

INSKEEP: It turned out to be a confused incident involving hunters and suspected border crossers. Nobody was hurt. Dob Cunningham says he cooperates with the Border Patrol and even admires many agents, but has come to doubt the agency as it grew in size.

CUNNINGHAM: They just hired too many riff-raff, crooks, thugs.

INSKEEP: His opinion of the Border Patrol reflects a larger doubt. An American flag flies outside his home. He's not sure it will fly here in the future.

So you think some day Mexico's going to move north?

CUNNINGHAM: I don't know that it will be - we may be like what's happening where you got the Russian's, you know.

INSKEEP: He's referring to Russia grabbing a chunk of neighboring Ukraine where many ethnic Russians live.

CUNNINGHAM: The culture and the patriotism will be strong as being a Mexican as being an American. You have Border Patrol in right now that don't know their allegiance to the United States. It's hard to believe but it's true.

INSKEEP: His evidence is that he thinks some current agents lack much ability with English.

CUNNINGHAM: There's people call me and say would you report this or that 'cause when I call they can't understand my English.

INSKEEP: Border Patrol agents are trained in Spanish, as is former agent Dob Cunningham. The Border Patrol has said its agents are, in fact, highly trained as well as, quote, "reliable, trustworthy and loyal to the United States." For all of his provocative claims, it is hard to form a simple view of the Texas rancher. Dob Cunningham keeps complicating the picture. He admits 98 percent of the border crossers who come through his property are just poor people who want a job.

Dob and Kay have sometimes fed them in their house. Not only that, Cunningham can point across the Rio Grande to the homes of Mexican friends.

CUNNINGHAM: Very close friends. They come and visit. I've waded the river right up from that house - his name is Tocho Garcia(ph) (unintelligible). I have waded the river and ate with him and visited him.

INSKEEP: Is that strictly legal if you just wade across?

CUNNINGHAM: Oh, no. No, if the Mexican army caught me, I'd still be over there.

INSKEEP: You'd be an illegal immigrant?

CUNNINGHAM: I'd be an illegal - trying to find somebody to buy me out.

INSKEEP: Dob Cunningham calls himself a border rat. He has absorbed the complexity of the borderland.

SIMON: That's our colleague, Steve Inskeep, whose road trip in the borderland continues tomorrow with the politician who wants less border security.

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