One year ago this week, Jared Lee Loughner pointed a Glock Safe Action Pistol at Rep. Gabrielle Giffords and shot her in the head. She fell to the ground; he turned, surveyed the parking lot where Giffords had been meeting voters, and emptied his 33-round clip into the first people he saw. Within two minutes he’d killed six and injured 17; he was only stopped when two would-be victims tackled him, one punching him in the face until he submitted.

This is painful to think about, but we’re lucky. Any national tragedy, given a little time and distance, can be shrunk down to news-cycle size. The one-year anniversary of “Tucson” generated three kinds of news. One: A stupid fight between the chairmen of the Democratic and Republican national committees—the Democrat, Debbie Wasserman Schultz, claimed to see “a very precipitous turn towards edginess and a lack of civility with the growth of the Tea Party movement.” Two: A new quest by Sen. Lisa Murkowski to ban partisan seating at congressional speeches. Three: Some touching TV specials about how Giffords herself was recovering and how the families of Loughner’s victims were dealing.

There’s a gaping gulf between the shooting itself and the glib remembrances that make it into the news. Tom Zoellner’s new book about the shooting, A Safeway in Arizona (Viking), almost fixes this. It’s a close call: Zoellner drives up to the border of some dangerous literary journalism clichés. He knew Giffords. She actually inspired him to quit his dull newspaper job and strike out as a long-form writer, and when she ran for Congress, he worked for her campaign. But he avoids the My Week With Marilyn-style “lessons a famous person taught me” trap. He psychoanalyzes Jared Lee Loughner, but he never claims to understand him. Zoellner’s a flawed, broken narrator, which saves the book from quick or pat answers.

“Loughner was not a tornado or an earthquake,” Zoellner writes. “He emerged from a specific human context.” The context is vast: It’s all of the cultural and political indicators that ruin Arizona. In Zoellner’s riskiest chapter, he remembers Tucson as a rotten place to grow up. “My skateboard was no good on those new asphalt streets. … I would sometimes steal into an unfinished house in the late afternoons to smash out the windows with rocks.” He’s not excusing Loughner, just describing what an isolated lifestyle in Arizona can do to people. The state ranks 48th among places where “people trade favors with neighbors” and 45th among places where people eat dinner with their families.

Loughner didn’t bring his Glock to the Safeway parking lot because he ate lonely dinners. The “nobody talks to anybody” theory is just the one that nearly every one of Zoellner’s interview subjects comes around to. The murders make Arizonans wonder if they’re leading mean, unexamined lives. Zoellner thinks they are: Isolation is slowly ruining Arizona, and ruining the rest of the country at a slower pace.

Of course, Zoellner never really deals with the ultimate nullifier of all arguments about violent crime: In the last few years, as a recession has groaned on and on and Americans have grown more isolated, the crime rate has actually declined. Something must be worse now, right? Zoellner hones in on a few things that have changed rapidly and—from the liberal’s perspective—horrendously. He talks with Jon Justice, a drive-time radio host who used to bully Giffords as socialist or socialist-enabler. “There is a blanket assurance in talk radio that one’s interests are being looked out for,” writes Zoellner, “that some brave body is finally calling bullshit and speaking the truth to power.” Well, yes: But in the very next paragraph, Zoellner admits that “there is nothing new about this in America.” In a book ostensibly about how something new and dark is happening to the country, Zoellner points out that Dallas, before JFK’s final visit, was roiled by right-wing conspiracy theories. “A report on the social context of Dallas in 1963,” writes Zoellner, “concluded that a pervasive culture of condoning violence as a way of settling disputes, as well as a competition to make outrageous political statements without shame or challenge, provided a logical arena for the sudden murder of a politician.”

Anyway, Loughner didn’t pay much attention to partisan chest-thumping stuff. “A close look at his Internet writings,” writes Zoellner, “shows that he was neither right nor left in any classic sense. His primary conviction was that a band of shadowy forces were manipulating ordinary people unaware of the deception.” This is important—an observation that was made last year but got much less play than the immediate and stupid partisan quest to blame the Tea Party for Loughner. But it’s only partly new. A schizophrenic (which Loughner seems to be) can seek out conspiracy theories about world government or lying language or Protocols of Elders with a couple of Bing searches. He’s finding material that’s been around for ages.

Zoellner realizes that Loughner was an even worse “theorist” than he was a fry cook. Toward the end of his wrap-up chapter, after listing eight “ifs” that could have prevented the tragedy (“if the state’s electoral system was configured in a way that rewarded those who tried to build coalitions” … “if there had been a federal ban on arm’s-length magazines that carry thirty-three bullets”), Zoellner wryly—maybe accidentally—throws his hands up. “The conversation that should have followed the Gabrielle Giffords shooting,” he writes, “was like that reckoning with race and inequality that was supposed to have started after Hurricane Katrina struck New Orleans.”

There’s never any reckoning. There’s only gawking and responsibility-dodging. Zoellner ends up blaming himself for this with a political anecdote. Maricopa County Sheriff Joe Arpaio’s cartoonish anti-crime tactics have made him a star, politically invincible at home. “I had been one of his many enablers,” writes Zoellner, apologizing for his old Arizona Republic stories. Zoellner meets up with Arpaio for a new interview and realizes what a sucker he was. “I loved it when you blasted me,” Arpaio tells him. “My polls went higher!”

Had Zoellner screwed up when he profiled Arpaio? Why did he give so much attention to the revenge-happy sheriff and not to Arizona’s withering public health system? Easy: The first story is easy to tell, and the second one isn’t. The first one allows everyone to sit in judgment and debate, and the second one is complicated. Solving it might not be possible; if it is, it’ll take a lot of money. Neither the problems nor the discussions are new. There’s just less and less time to get people’s attention. Wait too long, wait as long as it takes to publish a book, and they turn into the news cycle’s slow-witted cousin: trivia.