Fox News host Greta Van Susteren has provided extensive coverage of the case of Marine Sgt. Andrew Tahmooressi, who has been in a Mexican prison since April 1 on weapons charges. A veteran of two tours in Afghanistan, Tahmooressi says that he accidentally drove into Mexico at a San Ysidro border crossing, complete with a rifle (AR-15), a pistol and a 12-gauge shotgun, plus a great deal of ammunition. Along with colleague Bill O’Reilly, Van Susteren has pleaded for U.S. intervention on behalf of the Marine.

In an interview last night with quite-probable 2016 presidential candidate Hillary Rodham Clinton, Van Susteren asked, “What can the United States do or what should the United States be doing to help this Marine get fast-tracked through the judicial system because it was an accidental turn into Mexico?”

At which, Clinton broke out her diplomatic expertise:

We should be doing and I assume we are, you know, I’m not there, so I can’t speak directly to it — but we should be doing or I can tell you what I would be doing — burning up the telephone wires, sending, you know, envoys — not just our ambassador — but others coming in, talking to the highest level Mexican officials, making it clear that this is really important to us. You know, we work with our counterparts, our friends in Mexico on a lot of issues. Obviously, it’s something that is in our interest to do it as it is in theirs. When this kind of action happens and somebody who as you say made an accident turn who is serving our country ends up in a prison, that is just unacceptable.

After a bit more chatter on this topic, Van Susteren turned the conversation to Germany.

Thing is, Clinton’s pronouncements on this topic needn’t have been hypothetical. Van Susteren could easily have pressed Clinton on what she had actually done for a Marine imprisoned in Mexico on firearms charges. In August 2012, after all, a 27-year-old Marine veteran by the name of Jon Hammar crossed into Mexico with an antique shotgun and ended up in prison. The event occurred squarely within Clinton’s time serving as secretary of state.

Following Hammar’s detention, his mother, Olivia Hammar, alerted State Department headquarters, she tells this blog. Hammar would end up spending more than four months in confinement before his release around Christmastime 2012, an event that Olivia Hammar doesn’t attribute to Clinton’s leadership. “I would argue that the State Department abdicated in this case,” she says. “They did absolutely nothing.”

Rep. Ileana Ros-Lehtinen (R-Fla.), who represents the Florida community where the Hammars reside, lobbied for the Marine’s release with Mexican authorities, with her colleagues in Congress, as well as with the Obama administration — though not all avenues were equally productive. A statement from Ros-Lehtinen provided to this blog notes, “At first we tried it quietly with the Administration, but that wasn’t getting anywhere.” Did Clinton’s State Department burn up the telephone wires for Hammar? When asked about that matter, Keith Fernandez, a spokesman for Ros-Lehtinen, responds that his office is unaware of just what was done for Hammar. “All we know is that Jon had been in prison for months, since August 2012, and the Administration knew about it,” writes Fernandez via e-mail.

Another thing we know: Fox News turned the Hammar case into a high-profile affair just weeks before his Dec. 21, 2012, release. The story of Hammar’s confinement was broken by McClatchy on Dec. 6, and Fox News anchors quickly shuffled their story budgets to accommodate it. O’Reilly, Van Susteren and Sean Hannity — then the blockbuster prime-time trio on Fox News — devoted multiple segments to the case. In a Dec. 19 broadcast, O’Reilly was characteristically direct: “And what about the new Mexican President Nieto, where is he? He has the power to release Cpl. Hammar immediately. So why isn’t he doing it? This is a disgusting situation. And we call for President Obama to get Cpl. Hammar out of that filthy prison this week. The buck stops with you, Mr. President. Abraham Lincoln would have done it.”

O’Reilly’s assessment of top U.S. officials: “Secretary of State Clinton has done nothing and President Obama doesn’t even know about it, according to Jay Carney. That’s incredibly hard to believe as reports have been circulating for weeks.”

Olivia Hammar credits O’Reilly for keeping the focus on her son’s plight at a pivotal moment. On Dec. 14, 2012, she says, the attorney for Jon Hammar had a meeting scheduled with top Mexican officials about the case. That morning, the Sandy Hook massacre occurred; the Mexicans cancelled the appointment, for reasons that weren’t clear to Olivia Hammar. On the night of Dec. 14, O’Reilly devoted a segment of his show to the Hammar case, and pledged not to drop the matter: “Yes, we’re going to call for absolute boycott of travel to Mexico if he’s not out. Simple as that. Nobody goes,” said the host.

The next Monday, says Olivia Hammar, Mexican officials signaled their willingness to meet again. Hammar was released days later.

“Bill O’Reilly saved my son’s life,” says Olivia Hammar, who reports that Jon Hammar was very sick at the time of his release. “That’s the only reason he got home.” Ros-Lehtinen notes, “Bill O’Reilly was great; he was just tenacious — he knew the importance of getting Jon home immediately.”

Mexico challenges the cause-and-effect analysis. “No, Fox News was not instrumental,” says a senior Mexican official, who declined to address this matter on the record. “Neither Fox News nor any other type of press outlet, newspaper or social demonstration influences the decision on Mr. Hammar … or any other case because they are in the hands of the judiciary and the justice system of Mexico.”

Fox News anchors don’t necessarily share officialdom’s view of the Mexican system. Van Susteren: “I don’t trust Mexican police as far as I can throw them. They have a horrible history of corruption, many of them on the payroll of vicious drug cartels.” That rip came on Monday night’s edition of Van Susteren’s “On the Record” program, in reference to the Tahmooressi case. There’s a lot more such content: A search for “Tahmooressi” under Fox News yields more than 40 results — segment after segment chronicling the journey of this Marine into confinement south of the border. Van Susteren plays a central role in the coverage, having made a trip in May to the border crossing that bedeviled the Marine. She concluded that his story about accidentally steering into Mexico is plausible, as she reported in a May 21 discussion with colleague Sean Hannity: “It loops back down under the road. You go immediately into Mexico 100 yards away. There is a big cement barrier. There’s no U-turn, no change lanes, nothing. You make that wrong turn you’re in Mexico.”

In the early stages of his detention, Tahmooressi has claimed, he was beaten, deprived of food and water and shackled to his bed. Of late, he has received better treatment, which he attributes to news reports shining a light on his case, he told CNN.

When it comes to championing detained Marines, Van Susteren and O’Reilly appear locked in a healthy competition. “The O’Reilly Factor” recently sent Jesse Watters, a Fox News correspondent known for turning up the collar on his polo shirt in preparation for stupid-man-on-the-street interviews, to the Mexican consulate in Manhattan clad in a business suit. He had arrived to deliver a 180,000-strong petition seeking Mexico’s release of Tahmooressi.

The Marine’s bad luck in crossing the border with three firearms occupies a central theme in the petition of the “O’Reilly Factor” on behalf of Tahmooressi. The document reads: “Mr. Tahmooressi, a Marine reservist who has served his nation honorably … was arrested in Mexico after he mistakenly crossed a border point near Tijuana on March 31st . Since then, in spite of all evidence that he entered Mexico by mistake, the authorities in Mexico have not released him.”

When asked about the petition, a Mexican official wouldn’t even address it.

In a news release issued on June 6, the Mexican attorney general’s office laid out its side of the story, taking issue with key themes of the Fox News coverage. For instance, Tahmooressi had passed through the same border crossing near his arrest on three previous occasions, noted the release. “This information stands in contrast with his original statement in which he claimed it was the first time he had crossed at the location and had done so by mistake,” notes the document. Jill Tahmooressi, the jailed Marine’s mother, disputes the Mexican government’s version of events.

And that stuff about mistreatment? “The Attorney General’s Office reiterates its commitment to the observance of human rights and respect for due process of all those arrested, and rejects any assertion of mistreatment of Mr. Tahmooressi as baseless.” Also: Tahmooressi’s firearms can be carried legally in Mexico only by the military.

Fox News’s heavy focus on Tahmooressi stems from a clarity of mission. Of all news channels, Fox News is the home team for the military. Tom Ricks, a longtime Pentagon reporter, recalls that television monitors in the Green Zone media room during the Iraq war were commonly tuned into Fox News. “They thought that was their audience,” says Ricks, referring to the 2003-2004 time frame. “None of them had any idea what was happening beyond the Green Zone, and neither did Fox. It was like the blind leading the blind.”

Military holidays are taken seriously at the network. Last year for Veterans Day, for example, Fox News sent meteorologist Janice Dean to Florida to chronicle the efforts of Operation Shoebox, which sends care packages to the troops. Other segments discussed efforts to help disabled veterans and the job-search challenges of servicemen who’ve returned from the battlefield.

Affinity for all things military doesn’t always boost the network. As the Washington Post’s Bob Woodward reported, Fox News chief Roger Ailes passed a message to Gen. David Petraeus via Fox News analyst K.T. McFarland in 2011: Run for president if you don’t get the chairmanship of the joint chiefs of staff. McFarland told the general, “Everybody at Fox loves you,” and invited him to rewrite headlines that didn’t please him.

Perhaps fealty to the troops explains why some Fox News voices earlier this month ridiculed Robert Bergdahl, the father of recently released Taliban captive Army Sgt. Bowe Bergdahl — a soldier who left his base under mysterious circumstances in 2009 and spent five years as a prisoner of war. Some of Bowe Berghahl’s peers had questioned his actions; Robert Bergdahl grew a long beard and learned Pashto. Better to side with the soldiers than with the guy who “looks like a Muslim,” as O’Reilly put it.

And according to Media Matters for America, Fox News cares more about service members imprisoned in Mexico under President Obama than under President George W. Bush.

It’s hard, however, to take issue with Fox News’s work on behalf of these Marines. Consider the case of Tahmooressi: Two tours of duty in Afghanistan; a “rare combat field promotion to sergeant“; a reservist who’s committed until 2016; and a PTSD diagnosis for which he was seeking treatment in California.

How’s that for a case of meritorious media obsession? A Nexis search shows that McClatchy, CNN and the Los Angeles Times have covered Tahmooressi, but the case is hardly the preoccupation of the mainstream media. This is why we have media diversity — some outlets like the MH370 story, some like the Chris Christie bridge story, some like the story of Marines in trouble in foreign lands.

In a Web chat following a Bergdahl-related interview during the June 3 episode of “Fox & Friends,” Fox News host Steve Doocy talked about coverage of service members: “There are so many stories like that out there and nobody seems to tell those stories and that’s one of the reasons Fox is so widely viewed, because the military can count on us to do our best to tell their story.”

According to Fox News, Tahmooressi has been cycling through lawyers, clouding the resolution of his troubles in Mexico.

*Correction: Post originally misspelled the last name of Keith Fernandez.

Erik Wemple writes the Erik Wemple blog, where he reports and opines on media organizations of all sorts.