On a Saturday morning in late March, 58-year-old Robert Krentz was out checking a waterline on his family's ranch, a slice of Sonoran Desert once considered serene. He rode his Polaris ATV, with his dog at his side, two guns within easy reach. He was moving slowly, still recovering from a hip replacement and back surgery. At 10:30 a.m., his younger brother, Phil, received a radio transmission from him. Through static, Phil thought he heard Rob say "wind" and "illegal alien." A second man overheard the transmission and thought he heard Rob say "hurt." An hour and a half passed, and Rob stayed silent. They started looking.
The countryside made the search difficult: The 35,000-acre Krentz ranch sprawls in the San Bernardino Valley between the rugged Chiricahua and Peloncillo mountain ranges; one edge abuts the Mexican border. At 6:20 p.m., the family and friends called in law enforcement. Cochise County deputies, a state police helicopter, U.S. Border Patrol agents and ranchers scoured the valley for another five hours. Just before midnight, the helicopter crew found the missing man. He was still astride the ATV, slumped in the seat, with the headlights on, engine running. He and the dog were dead from gunshot wounds. His guns were still holstered. Spin-out tracks scarred the earth, suggesting that he'd tried to get away after he was shot.
Around dawn, trackers with dogs found what they believed to be the killer's footprints. They followed the tracks to the Mexican border, near an extinct volcano called Cerro Gallardo in Mexico and Niggerhead Rock in Arizona. Like so many real and mythical desert coyotes, the killer had vanished.
It is my belief that our suspect was across the line, probably before we ever got on his track," says Cochise County Sheriff Larry Dever. "The guy had almost a 20-hour head start."
The investigation into the killing remains open; no suspects are in custody. Yet many people quickly concluded that it was either the result of Mexico's notorious drug-cartel wars or an escalation of the problems associated with illegal immigration. No local murder had been blamed on illegal immigrants in the past 10 years, so it was especially hot news. Republican legislators used it to gain backing for Senate Bill 1070, which instructs Arizona law enforcement to check the citizenship papers of any person they contact who appears to be in the country illegally. State Sen. Russell Pearce, who introduced the bill, wrote, "The murder of Robert Krentz -- whose family had been ranching in Arizona since 1907 -- by illegal alien drug dealers was the final straw for many Arizonans." The Legislature passed and Republican Gov. Jan Brewer signed the bill within a few weeks. Even as civil-rights advocates denounce it as racist and unconstitutional, opinion polls show that some 70 percent of Arizonans support the crackdown.
The killing also spurred a military buildup reminiscent of 1914, when President Woodrow Wilson ordered 5,000 troops to contain the Battle of Naco, a conflict between factions in the Mexican Revolution. About 20,000 Border Patrol agents are already stationed along the entire Mexican border, but within a few days of the killing, Democratic Congresswoman Gabrielle Giffords of Tucson asked the Department of Homeland Security to add National Guard troops. "This cold-blooded murder is a sober reminder that the safety of U.S. citizens on American soil is under attack," she wrote. President Obama took action in late May, ordering 1,200 troops to the border and an additional $500 million in border protection funding. Republican Sen. John McCain, campaigning for re-election, says 1,200 is not enough; he wants 6,000.
Even the nation's regular military forces have joined the crackdown. In mid-May, two F-16 Fighting Falcons were scrambled out of Davis-Monthan Air Force Base near Tucson to intercept an ultra-light plane that had flown in from Mexico, on the suspicion it contained smuggled drugs.
It remains to be seen whether the increased vigilance is a long-term investment in improving border security or merely a political strategy to quell short-term panic. Either way, the response to the killing is the clearest sign yet of how, over the past decade or so, national and international forces have changed the atmosphere of this once-quiet rural area.