It has been a while since we heard directly from "the architect of global jihad," "the mufti of murder," the apostle of "individualized terror" known by his nom de guerre Abu Musab al-Suri. Indeed, most people outside jihadist circles have never heard of him at all.

But thanks to the shadowy practices of the Bush administration in its global war on terror, this Syrian-born former adviser to Osama bin Laden is now at large— and an inspiration to a whole new generation of killers, including, it would seem, those in Boston and London.

And these attacks do not look as if they are likely to stop any time soon. Over the weekend, a French soldier on anti-terrorist patrol at the La Defense transport hub and shopping center on the outskirts of Paris had his neck slashed by a tall, bearded assailant who has yet to be apprehended.

Al-Suri, a continuing inspiration to terrorist far and wide, had a core strategy which was detailed in a 1,600-page treatise, The Call for an International Islamic Resistance. He encouraged opportunistic and improvised terrorist acts in the West, sapping the public's morale and undermining the ability of the American, British, French, or other armies to fight on Muslim soil. But it is such a thorough guide to the philosophy and techniques of terror that crazies far outside the realm of Islam have adopted it. Anders Behring Breivik, the Muslim-hating "lone wolf" who murdered 69 people in Norway in July 2011, studied Al-Suri's lessons closely.

I wrote about Al-Suri in detail in 2007, after an interview with Al-Suri biographer Brynjar Lia, author of Architect of Global Jihad. Yet after the proliferation of "lone wolf" attacks in recent years, and indeed in recent weeks, it all seems much more relevant.

Al-Suri was not a big advocate of suicide bombings. He was unimpressed by huge spectaculars. He wanted to substitute quantity for quality in the terror business. He mistrusted empty-eyed religious fanatics whose suicidal goal was to get to Paradise. "What is important," said Lia, "is the impact in terms of confusing, paralyzing and terrorizing the enemy."

In 2005, the Pakistanis captured Al-Suri and reportedly turned him over to the Central Intelligence Agency. How long and where the agency held him is not known to the public, but eventually he was "renditioned" to the tender mercies of the Syrian security forces serving President Bashar al-Assad. Yes, that Bashar al-Assad.

At the time, the CIA was trying to maneuver a delicate relationship with Damascus, which involved the kind of cynical commerce in lives that John Le Carré often writes about. The Syrians were a problem. They were facilitating the flow of radical jihadists into Iraq who were blowing up Americans and their allies by the hundreds. But it was assumed the Syrians didn't really like al Qaeda; they just wanted to use its minions to stir up trouble for their enemies. At the same time, Washington was looking to enhance its own cooperation with Damascus. Throwing the skin and bones of Al-Suri to Assad's minions would be one way to do that. What the deal was precisely we may never know, but if Congress wants to investigate a critical mistake in the fight against al Qaeda, the Al-Suri case would be a good starting point.

According to intelligence officers serving in the region at the time, the CIA had a fairly extensive liaison relationship with some of the Syrian services, of which there are many. (Much of their work is to watch each other.) As often happens, storms could break over the diplomatic ties without breaking the clandestine ones. Agreements were reached, information garnered.

But after the Arab Spring revolts at the beginning of 2011 led to a popular uprising in Syria, all bets were off. Assad's thugs tortured and mutilated little boys and called them terrorists. They insisted their enemy was al Qaeda and similar jihadists, which struck many experienced intelligence officers as ironic considering the games Assad played with them a few years earlier.

The Obama administration, after first hoping that Assad could maneuver himself into the position of a reformer, finally gave up and started calling for him to step down. But Assad continued with the global-war-on-terror mantra that had served his duplicitous ends with the Bush administration. Apparently to fulfill his own prophecy—and signal Washington he would no longer play ball, even in the shadows—in January 2012 Assad let Al-Suri and one of his top aides walk free.

Now, for the conspiracy-minded—and who in the world of Mideast intelligence services is not conspiracy minded?—this is where things get really interesting. (Le Carré, take note.)

"It's a mystery where Al-Suri is, but I wonder if he could be trusted by his former comrades," says French scholar Gilles Kepel, author of Beyond Terror and Martyrdom. Al-Suri had been held for seven years in some of the cruelest prisons in the world: the Pakistanis', the CIA's and the Syrians'. Among their technicians are expert manipulators of fear and hope. Conceivably, Al Suri could have been sent back into the ranks of the jihadists the way the soldier-hero of the television series Homeland was sent back to America: programmed to betray. Indeed, Al-Suri may be more useful to al Qaeda at this point as a legend than as a living ideologue. But there is no question that his ideas are gaining ground in places such as Indonesia, France, Britain, and the United States. And it is conceivable that he is playing a more direct role in the spreading incidents of supposed lone-wolf terror.

As President Barack Obama made abundantly clear in his national-security speech on Thursday, much thought and lawyering went into the hunt for American-born Qaeda propagandist and terror plotter Anwar al-Awlaki, terminated on the president's orders in a death-from-the-skies fireball two years ago. Another U.S. citizen killed with Awlaki was Samir Khan, editor of the online magazine Inspire, a DIY guide to bomb-building and mayhem-making that might as well be called Terrorism for Dummies. Among its readers? The Tsarnaev brothers, who allegedly attacked the Boston Marathon.

Awlaki and Khan "would not have been able to accomplish what they did without Suri's body of work," wrote Jarret Brachman, a former director of West Point's Center for Combating Terrorism, shortly after Al-Suri's release. "Awlaki was never the arch nemesis that we painted him to be. Yes, he was compelling for the global media to hype ... But he was painting by number on a worksheet that had been already drafted by Suri. Samir Khan just helped to translate that image into digital pixels."

Born Mustafa bin Abd al-Qadir Setmarian Nasar in 1958 to a prosperous family in Aleppo, al-Suri (the Syrian) was educated as a mechanical engineer but quickly fell in with the revolutionary elements of the Muslim Brotherhood. In 1980, before Assad's father and uncle crushed that organization's uprising in the 1982 devastation of Hama, al-Suri had gone into exile. He traveled widely and blended in easily, especially in Europe, where his red hair, fair skin and blue-green eyes gave no hint of an Arab background.

In the 1980s and ’90s, Al-Suri spent time in Jordan and Iraq, Spain (where he married and became a citizen), Afghanistan (where he trained fighters and worked his way up in the councils of Bin Laden as, not least, a media adviser), France, and "Londonistan" in Great Britain, where he worked closely with Algerian revolutionaries.

By 1998, Al-Suri was back in Afghanistan collaborating with the Taliban. After their defeat in 2001, he fled to Iran, where he was briefly arrested, then went to northern Iraq for a while, apparently hanging out with the Jordanian terrorist Abu Musab al-Zarqawi, famous for a series of suicide bombings and beheadings. Al-Suri denied any role in 9/11, the Madrid bombings of 2004 or the London subway bombings of 2005. But he applauded them all. One of his most cherished goals, he said, was to see the United States attacked using explosives laced with radioactive materials: "A dirty bomb for a dirty nation," as he put it.

The French soldier attacked over the weekend has been released from hospital, but the box-cutter slash on his neck could have been fatal. It only missed his carotid artery by an inch. It appears that a similar attack took place in Roussillon, in southeast France, on May 7, when a man shouting “Allah is great” attacked gendarmes, also with a box cutter, and injured one before being shot and wounded. At the time, the incident barely made the regional press. The French government has been careful not to prejudge the identity of the assailants or their motives. But Interior Minister Manuel Valls did say this week that France faces a growing threat from an "enemy within." If so, the teachings of Abu Musab al-Suri share part of the blame. What the man himself is up to, sadly, remains to be seen.