Khalid Shaikh Mohammed at his capture in 2003, left, and in a photo said to have been taken at Guantánamo in 2009.

By JONATHAN MAHLER

Published: July 6, 2012

More than a decade after 9/11, it seems safe to say, the global war on terror has been both an extraordinary success and a colossal failure.

1- THE HUNT FOR KSM

Inside the Pursuit and Takedown of the Real 9/11 Mastermind, Khalid Sheikh Mohammed

By Terry McDermott and Josh Meyer

2- HUNTING IN THE SHADOWS

The Pursuit of Al Qa’ida Since 9/11

By Seth G. Jones

First the good news: Since Sept. 11, 2001, the day the war unofficially began, Islamic extremists have killed just a handful of Americans on United States soil, nearly all of them members of the military. Al ­Qaeda is in retreat. Through the use of covert intelligence, special operations and drone strikes, we’ve managed to take down or take out many of its senior leaders.

At the same time, our intelligence agencies have demonstrated an almost mind-boggling inability to work together. We invaded Iraq, spending hundreds of billions of dollars on a long military campaign that claimed thousands of American lives and played right into the hands of our enemies by uniting Al Qaeda and the Iraqi insurgency. We tortured prisoners, not only staining our nation’s reputation but surely swinging more young Muslims to the cause of radical Islam than any Qaeda recruiting video ever could. We are still fumbling with how to try captured combatants, and what to do with those whom we don’t want to, or can’t, prosecute.

“The Hunt for KSM,” an in-depth account of the pursuit and capture of the architect of 9/11, Khalid Shaikh Mohammed, gives us the war on terror at its best and worst. Here we have the story of dogged agents painstakingly cultivating intelligence and running down every semi-credible lead as they chase one of the world’s most dangerous terrorists across the globe.

We also have the story of the bureaucratic infighting that may well have delayed Mohammed’s capture and certainly ensured that the agents who knew him best — the ones most likely to be able to recognize when he was telling the truth and when he was lying — were nowhere in sight during the first three years of his interrogations in Pakistan and at a series of secret prisons.

At the center of this intragovernmental warfare are two familiar antagonists, the Central Intelligence Agency and the Federal Bureau of Investigation, with their fundamentally different approaches to terrorism, epitomized by their reactions to 9/11. “The F.B.I., looking at the smoldering ruins in New York . . . reflexively asked: What happened?” the authors write. “The C.I.A. was far better at looking past the disaster that had occurred and asking the defining question of the period: What next?”

As turf wars go, it wasn’t much of a fight. In the wake of 9/11, when the need to prevent another attack was pretty much all that mattered, the C.I.A. instantly became America’s pre-eminent antiterror agency, and the F.B.I., with its years of hard-earned knowledge of radical Islam, was shunted aside. In the case of Khalid Shaikh Mohammed the result was especially tragic, according to Terry McDermott and Josh Meyer, both former journalists with The Los Angeles Times; it meant that Francis J. Pellegrino, an F.B.I. agent who had been obsessively tracking Mohammed since the World Trade Center bombing in 1993, was essentially cut out of the loop.

When Mohammed was betrayed to the C.I.A. by an old friend and chased down to a safe house in Rawalpindi, Pakistan, in early 2003, Pellegrino was asked to provide a list of questions to his interrogators, private C.I.A. contractors with no particular expertise in Al Qaeda. He declined. (“I don’t write questions,” he said. “I ask questions.”) The rest of the story should have been easy to predict: Mohammed provided his interrogators with a lot of bad information in order to get them to stop torturing him.

The two authors of “The Hunt for KSM” have reconstructed an almost decade-long clandestine manhunt in exacting detail, an undeniably impressive feat of sleuthing. Narrative velocity is not a problem either; from beginning to end, “The Hunt for KSM” moves along at the brisk pace of a good crime novel. Where the book falls short is in the depth and intimacy of its portraiture. McDermott and Meyer present a tantalizing cast of characters — most notably Pellegrino, a former accountant, and Mohammed, a modern-day Carlos the Jackal — but never quite bring us close to any of them.

The subtlety and imagination of the writing don’t always live up to the doggedness of the reporting, which can drain the emotional power from otherwise dramatic moments, as when Pellegrino finally finds himself sitting opposite his nemesis in an interrogation room at Guantánamo Bay. “Pellegrino thought K.S.M. might be the kind of guy you could sit down and have a beer with, if he hadn’t been one of the worst mass murderers in American history,” the authors write.

1- THE HUNT FOR KSM

Inside the Pursuit and Takedown of the Real 9/11 Mastermind, Khalid Sheikh Mohammed

By Terry McDermott and Josh Meyer

2- HUNTING IN THE SHADOWS

The Pursuit of Al Qa’ida Since 9/11

By Seth G. Jones

Seth G. Jones’s “Hunting in the Shadows” provides a wider-angle view of the war on terror. Rather than zeroing in on the hunt for a single bad guy, Jones, a former senior adviser at United States Special Operations Command, seems determined not to leave any out. The result is exhausting, a seemingly endless rogues’ gallery of terrorists and their American pursuers since 9/11.

But if “Hunting in the Shadows” can at times make for slow reading, it is an important book, though less for the individual stories it tells than for the broader analysis Jones uses to frame them. As he sees it, the history of Al Qaeda’s war against the Western world can be best understood as a series of “waves.” The first started with the embassy bombings in East Africa in 1998, crested on 9/11 and ended with allied forces striking back against Al Qaeda’s leaders in Afghanistan, Pakistan and elsewhere. The second began in 2003, after the American invasion of Iraq, and ended when a growing number of tribal sheiks in Iraq turned on Al Qaeda. The third rose between 2009 and 2011, driven by the emergence of the radical cleric Anwar al-Awlaki in Yemen, and concluded with the killing of Osama bin Laden and several other Qaeda leaders last year.

Studying these waves, and the counterwaves that repelled them, can tell us a lot about what works and what doesn’t when it comes to fighting terrorism. Most fundamentally, we have learned the hard way that the war on terror isn’t really a war — that if we attempt to defeat Al ­Qaeda by deploying large numbers of conventional soldiers to foreign countries we are only likely to create a backlash of ­radicalization.

Instead, Jones explains, we should rely on “a light-footprint approach” that favors special operations and intelligence-­gathering. We should help local governments to establish basic law and order in unstable areas where Al Qaeda is threatening to grow roots. And we should wage our own propaganda battle against Al Qaeda, one that emphasizes the organization’s indiscriminate murder of civilians. The war on terror, Jones writes, “is a war in which the side that kills the most civilians loses.”

President Obama recently declared that victory over Al Qaeda was “within our reach,” and that the time had come to refocus the nation’s energy and resources on domestic affairs. Let’s hope he’s right. But if he’s not, and a fourth wave is still to come, he and his successors in the White House would do well to keep these lessons in mind.

Jonathan Mahler is the author, most recently, of “The Challenge: How a Maverick Navy Officer and a Young Law Professor Risked Their Careers to Defend the Constitution — and Won.”