In the 14 years since the 9/11 attacks, the face of terrorism has changed out of recognition. To many experts, the threat of Islamist terror is in some ways greater and in some ways diminished. It is geographically more diverse and organizationally more divided, and leverages social media and the internet in a way impossible in 2001.
In the West, Islamist terrorism is often more inspired than organized and directed. Its menace is also more fluid and unpredictable than it was on that bright autumn morning in 2001, but the tools to combat it are also more plentiful, from ever more sophisticated and accurate drones to financial intelligence and algorithms for chewing terabytes of data in the pursuit of suspicious communications.
The likelihood of an attack on the scale of 9/11 has receded. but the probability of more frequent though less devastating attacks has increased.
Who's in charge?
As if on cue, al Qaeda has just released a 45-minute lecture by its leader Ayman al-Zawahiri that illustrates just how much has changed. Fourteen years ago, al Qaeda was the undisputed heavyweight among jihadist groups, even more so after the 9/11 attacks. Today al-Zawahiri, who succeeded Osama bin Laden in 2011, is struggling to fend off the new pretender, the Islamic State in Iraq and Syria (ISIS).
In his latest message, he launches a broadside against ISIS and its leader, Abu Bakr al-Baghdadi. "We do not acknowledge this Caliphate, and we do not see it as Caliphate on the prophetic method; instead, it is an emirate of taking over without consultation," complains al-Zawahiri.
Al Qaeda has always seen its campaign as a generations-long struggle toward the glorious day when a Caliphate could be declared -- based on Islamic prophecies. Then -- in 2010 and 2011 -- al-Baghdadi rebuilt ISIS from the ashes of al Qaeda in Iraq, extended its field of operations to Syria (2012), and declared himself the Caliph of all Muslims (2014.)
And so battle is joined between two heavyweights of the jihadist movement in a way unimaginable 14 years ago. Both have their MVPs.
Al Qaeda has the brilliant bomb-maker in Yemen, Ibrahim al Asiri, and a commander in Afghanistan called Farouq al Qahtani who is regarded as smart and charismatic. ISIS has a whole raft of potential contenders should the unthinkable happen to al Baghdadi.
It would seem that two jihadist groups battling each other would be good news, and al-Zawahiri makes no attempt to camouflage his loathing for al-Baghdadi in his latest speech. But right at the end of it, he says this: "Despite these grave mistakes, were I in Iraq or in Sham [Syria] I would cooperate with them [ISIS] in fighting the Crusaders, the secularists, the Nusayris, and the Safavids, despite my not acknowledging the legitimacy of their State, not to mention their Caliphate, because the matter is bigger than me and their claim of establishing a Caliphate."
An olive branch? An attempt to win over rank and file ISIS members? Muddled thinking? No wonder intelligence professionals find the current landscape more difficult to analyze than that of a decade ago.
Similarly unimaginable 14 years ago is that a jihadist group -- a "nonstate actor" as the academics say -- could control a huge amount of territory. Al Qaeda was the guest of the Taliban in Afghanistan, and after 9/11 was dispersed to mountain camps in Pakistan. Al-Shabaab, for a while, controlled parts of central and southern Somalia; al Qaeda in the Islamic Maghreb briefly held some towns in Mali.
But these groups never had the trappings of a "state" in the way ISIS has Sharia courts, basic social services and now even a currency. And any form of safe haven allows for greater and more ambitious planning.
Nick Rasmussen, the director of the U.S. National Counterterrorism Center, says "access to resources, both personnel and monetary resources; control of territory, which allows for the creation of a safe haven -- those are the ingredients that we traditionally look at as being critical to the development of an external operations capability."
Interviewed in the Combating Terrorism Center's latest edition of the Sentinel, Rasmussen says there is a "watching brief" on whether ISIS is planning to open a new front in Europe and the United States. But as the U.S. military presence in Afghanistan winds down, he says that the NCTC is also trying to assess "what level of risk we may face over time that al Qaeda may regenerate, find renewed safe haven, or be able to restore lost capability."
On 9/11, al Qaeda had its camps in Afghanistan; there was a jihadist presence in Algeria and the Caucasus and some budding militancy in the Arabian Peninsula. Now jihadist groups from Indonesia west to the African shores of the Atlantic declare their allegiance to either al Qaeda or ISIS.
Former CIA Acting Director Mike Morell says that al Qaeda's "great victory has been the spread of its ideology across a large geographic area" from northern Nigeria across Africa and into Yemen" as well as to Iraq and Syria.
Writing in the latest edition of the Combating Terrorism Center's Sentinel, Morell says that "all told, some 20 countries now have terrorist groups within their borders espousing the jihadist ideology."
And ISIS has created "provinces" beyond Syria and Iraq at warp speed.
There are countless more "no-go zones" in the world than there were on 9/11:
-- Britain tells its holidaymakers to avoid Tunisia.
-- Parts of Kenya and Egypt are off-limits, as is almost all of Libya.
-- Boko Haram has turned much of northern Nigeria into a battlefield (as well as some areas of neighboring states.)
-- Yemen was never the easiest place to navigate but has imploded in the past four years, becoming yet another theater in which al Qaeda and ISIS compete to kill the most Shiites.
And in Syria, a regime once regarded as the most unshakeable in the Middle East, has lost control of much of its territory, with millions of its citizens displaced.
Rasmussen says "the array of extremist terrorist actors around the globe is broader, wider and deeper than it has been at any time since 9/11."
"It's fair to say that we face more threats, coming at us from more places, involving more individuals than we have at any time since 9/11," he says.
Inspired, motivated or directed?
The nature of the threat has also changed. According to former al Qaeda insiders, the planning for the 9/11 attacks by Abu Hafs al Masri and Khalid Sheikh Mohammed began fully two years beforehand. The resources devoted by the United States and its allies since 9/11 to deterring attacks on the homeland -- everything from enhanced airport screening to no-fly lists to a massive increase in the amount of data collected and analyzed -- makes another such spectacular attack more unlikely.
But so diffuse is the threat now, and so much greater the appeal of ISIS to some who live in (or have left and then returned to) Western countries, that a stream of smaller but still deadly attacks has become the norm. This year alone, terrorist attacks in France and Tunisia have killed more than 70 civilians.
That's a function of -- for want of a better word -- devolution by terror groups such as al Qaeda and ISIS to individual supporters, often known as lone wolves or cells of two or three. There is now a somewhat blurred spectrum from the inspired and self-radicalized at one end to the attack planned and directed by a group's leadership at the other. And the results are mixed.
The Kouachi brothers, who attacked the Paris offices of Charlie Hebdo in January, had been with al Qaeda in Yemen four years previously, but they made all the operational decisions themselves, with deadly effect.
The attempted attack on an exhibition of cartoons of the Prophet Mohammed in Dallas also appears to have been encouraged by an ISIS "cheerleader" but was poorly planned and left only the two assailants dead.
Even so, Rasmussen says that "the "flash to bang" ratio in plotting of this sort is much quicker and allows for much less time for traditional law enforcement and intelligence tools to disrupt or mitigate potential plots." And that, he says, is a great challenge.
The terrorist diaspora
It's a challenge heightened by the sheer numbers of individuals from Western countries who have slipped into Iraq and Syria in the past few years.
Mike Morell predicts that an attack in Europe or the United States directed by ISIS (as opposed to inspired) will eventually occur. It might be small-scale "but over time the Islamic State's capability to conduct a more complex attack will grow."
That's not least because of the estimated 5,000 Westerners who have gained battle experience and skills with bombs and weapons after joining ISIS. Al Qaeda always attracted a few from the West, such as the American Adam Gadahn and a number of British citizens of Pakistani origin. But not on the scale of ISIS, which may have attracted as many as 25,000 foreign nationals to Iraq and Syria.
Rasmussen says that following the break-up of a terror cell in Belgium earlier this year, there is concern that ISIS operatives in Iraq and Syria may be pivoting toward directing attacks in Europe. For now, the group appears largely focused on consolidating the Caliphate, drawing fighters in rather than sending them out. But Western counterterrorism officials know that could change.
Social media and communication
In the run-up to and years immediate after 9/11, occasional pronouncements from al Qaeda would emerge via television networks such as Al Jazeera. The occasional statement from Osama bin Laden would be scrutinized for any clues as to his health, location or strategy.
Now ISIS has a full-blown propaganda machine in several languages, releasing video, photographs and daily news bulletins. Production is of high quality, dissemination wide through Twitter accounts and jihadist websites. A large number of ISIS supporters use Twitter, whether to incite attacks overseas, lure jihadist 'brides' to the Caliphate or relay news and photos of military operations.
It also has IT experts capable of what's called end-to-end encryption. Talking to the Sentinel, Rasmussen says one of the great worries today is "terrorist groups' innovative and agile use of new means of communicating, including ways which they understand are beyond our ability to collect."
The long run
One thing perhaps has not changed since the aftermath of 9/11, and if anything, it has become clearer. Western intelligence officials used to speak of the task of degrading al Qaeda over a number of years. Now the same language is used of both al Qaeda and ISIS -- except that officials speak in terms of decades or a generation rather than mere years.
And the prescriptions for combating these groups in a war of ideas also sound remarkably similar. Morell says the West "must address the issues that create terrorists in the first place. ...We must undermine the jihadist appeal to young Muslims."
It's been difficult. Many of the same problems that afflicted the Arab world in 2001 are still present and have been aggravated by the upheavals of the Arab Spring. The outgoing Chairman of the Joint Chiefs of Staff, Gen. Martin Dempsey, speaks of "pervasive instability, disenfranchised groups, ethnic conflict, [and] religious conflict in the Middle East and North Africa that will take a decade or more to resolve."
"We are likely to look back at the last 14 years as only the opening salvo in what will be a very long war."