TWILIGHT ON THE LINE: Underworlds and Politics at the U.S.-Mexico Border.

By Sebastian Rotella. Norton. 320 pp. $25

A book blurbed by Bruce Springsteen ("Rotella’s passionate reporting on the street kids of San Diego led me to write ‘Balboa Park’ " ) may not immediately inspire scholarly confidence. Is this yet another pop dramatization of a complicated policy issue? The fear is unfounded. Rotella, who covered the U.S.-Mexico border for the Los Angeles Times from 1991 to 1996, reveals the violence and tragedy unfolding in a region at once very close and very far away. Some of the events he recounts have made headlines. But most Americans, including most elites, have yet to come to grips with them. This evenhanded book will help.

Rotella begins by portraying the dangers endured by the hundreds of thousands of illegal aliens who continue to stream into the United States. Not least among the perils is mistreatment at the hands of the criminal rings that smuggle people across the border. As Rotella points out, long-thriving smuggling rings have become even more profitable recently, thanks to American efforts to stem illegal immigration: fees have jumped from about $350 to as much as $1,000 per person for the trip from Mexico. While most immigration researchers have yet to factor smuggling into their analyses, Rotella wisely places it at the center of his account.

Rotella argues that the much-publicized border fence has not so much stopped the influx as redirected it to remote parts of the border where no fence has been built. Still, Rotella acknowledges that the fence has imposed order on what was verging on a Hobbesian state of nature. As recently as the early 1990s, the nightly scene a few minutes from downtown San Diego was one of border bandits robbing, raping, and murdering migrants. And the migrants, massed by the hundreds waiting to make their move, were themselves known to assault U.S. Border Patrol agents.

The violent heart of Rotella’s account begins with the 1988 murder of a crusading Tijuana journalist and continues with the 1993 assassination of Cardinal Posadas of Guadalajara. In late February 1994, two Mexican drug traffickers with ties to the presidential campaign of Luis Colosio, presumptive successor to President Carlos Salinas, were shot while driving on Interstate 5, 75 miles north of Los Angeles. Days later, a machine-gun battle between federal and state police in a middle-class Tijuana neighborhood left five dead. Three weeks after that, presidential candidate Colosio was assassinated, apparently by a lone gunman, in a shantytown outside Tijuana. In April, the reform-minded chief of the Tijuana police was gunned down. And in January 1997, the special prosecutor investigating that murder was assassinated at his home; four gunmen riddled his body with more than 120 rounds and then ran over it with their van.

The link between these bloody events is of course the drug trade, specifically the battle among rival clans to control the lucrative

U.S. market. In typically incisive fashion, Rotella asks whether the drug smugglers may be connected to the alien smugglers. His answer is no, at least not yet. But to read this remarkable book—all the more remarkable for its complete avoidance of moralizing, invective, sensationalism, and off-the-cuff policy prescriptions—is to feel confident that should this precarious situation change, Rotella will be the reporter who brings us the news.

—Peter Skerry