The next Islamist militant terrorist to strike us may not fit the profile of a "usual suspect." He may not be an Arab or part of a well-structured Islamist cell, but rather, a loner from a non-Arab country, perhaps a foreign-born, middle-class, seemingly well-integrated engineering graduate, or a business school student.
He might be as American as apple pie, or a convert to Islam, especially of Hispanic origin. He may rarely attend a mosque, but spend hours on the Internet. And he may turn out to be a she.
Several of the nation's best counterterrorism experts say that based on the patterns of attacks in the past two years and the evolving nature of the militant Islamist threat, those seeking to prevent the next attack against Americans at home or abroad should expect the unexpected.
Most analysts agree that the most encouraging news is that al-Qaida core and its most historically prominent affiliates, such as al-Qaida in Iraq, are under such enormous military and counterterrorism pressure that they probably cannot mount another catastrophic attack like 9/11 against the United States, or American targets in Europe and elsewhere any time soon.
But then there are more ominous developments.
First and foremost, al-Qaida seems to have metastasized into many, only temporarily less lethal organizations.
Bruce Hoffman, a leading terrorism analyst at Georgetown University, says that the growth of what he calls the "al-Qaida universe" in the past two years is now well-documented and extremely worrisome. Whereas there were seven al-Qaida networks or theatres of operation in 2008, he said, there were 11 last year — a growth rate of over 50 percent," he says.
Moreover, the universe could expand even further and faster given the growing number of failed and failing states — vacuums that attract such groups.
Such politically weak states as Yemen and Somalia are now hosting groups like al-Qaida in the Arabian Peninsula (AQAP) in Yemen and Somalia's Al Shabaab.
Brian Jenkins, the nation's veteran counterterrorism guru at Rand, says, for example, that Yemen, in particular, has become "an important launch site for truly global terrorist organizations."
Once a decidedly second-tier group in terms of capability and ambition, AQAP has grown ever more lethal in reach and ambition, if not yet in capability, as the failed Christmas bombing plot of 2009 and effort to place two bombs in cargo flights originating in Yemen late last year show.
These trends lead Hoffman to conclude that there is a "high likelihood" of a terrorist attack in the U.S. and that the next bomber is likely to have more than the five days of bomb-making training that Faisal Shahzad had, referring to the naturalized Pakistani-American who tried to blow up his SUV in Times Square last May.
Hoffman, among others, worries about America's inability to deter al-Qaida and its allies despite the damage being inflicted on the militants' leadership by the continued Predator and drone attacks in northern Pakistan.
Finally, he sees another trend: the growing prominence of Americans in al-Qaida and like-minded terrorist groups.
For the first time, Americans are senior figures in al-Qaida or its close allies — Adnan Gulshair el-Shukrijumah, a 36-year-old Saudi and naturalized American former school teacher who is now believed to be al-Qaida's chief of operations; Omar Hamami, an Alabama-born convert to Islam who is an Al Shabaab commander; and Anwar al-Awlaki, the Yemeni born U.S. citizen and Muslim cleric whose internet sermons have inspired recent Islamist terrorists, and who is now a key figure in AQAP in Yemen.
Among the most ominous trends is the phenomenon initially identified in a 2007 New York Police Department report co-authored by Mitchell Silber, who now oversees the NYPD's intelligence analysts.
In 2009 at least 43 U.S. citizens or residents were charged or convicted of terrorism crimes, according to Hoffman's count; at least two dozen Americans figured in terrorist plots last year.
At a public briefing for private security representatives last winter in New York City, Silber warned that there were likely to be more "homegrown" plots ahead in Europe, the United States, Canada, and Australia.
Another new trend is the growing role of the Internet as a medium of radicalization, says Silber. At least two plots last year, for instance, were inspired by Inspire, a glossy jihadi GQ, an online magazine in English that is targeted at the audience Islamist militants most desire, Americans and other English-speakers who can blend into western culture.
Inspire features interviews with jihadi heroes and militant "self-help" articles like "How to Make a Bomb in the Kitchen of Your Mom."
Major Nidal Hasan, whose savage attack on his fellow soldiers at Fort Hood, Texas killed 13 and wounded more than 30, tried to communicate through e-mails with cleric al-Awlaki, in Yemen, and Silber says that the Internet, and Facebook in particular, is increasingly a preferred medium of communication among jihadis.
In other words, some of those exchanging messages on social networking sites are not seeking to be any American's "friend."
Mitch Silber and Karen Greenberg, the executive director of the Center on Law and Security at NYU's law school, assert that converts to Islam increasingly feature in jihadist plots. "We're not really sure why," she said in a recent interview.
Another trend is the emergence of women in terrorism. According to a study last year by the Anti-Defamation League, the number of American women charged with involvement in terrorism has doubled within the past year.
In addition to planning terrorist plots, American women have allegedly raised funds and provided material support to such foreign terrorist groups as Hezbollah and al-Qaida-linked affiliates.One need only think of "Jihad Jane," Colleen LaRose, indicted for her role in planning to murder a Swedish cartoonist whose depictions of the Prophet Muhammad offended the militants.
Marc Sageman, a forensic psychiatrist and former CIA and Foreign Service officer whose book, "Leaderless Jihad," is highly regarded among counterterrorism analysts, has identified yet another trend — the growing number of "loners" involved in such plots.
On one hand, that is likely to make the plots less sophisticated and deadly; on the other, it could make the would-be plotter harder to spot and monitor. "The blob is disorganized, not coordinated, amateurish, getting more and more to a state of 'leaderless jihad,' as I had predicted three years ago," he recently wrote in an e-mail.
Finally, Brian Jenkins sees a trend in the return of anarchists in Europe. "They never really went away," he wrote in an e-mail. "But stay tuned for more bombings" from groups like Irish Republican Army dissidents. "They never really went away," he writes, "But they're definitely back."
Put these trends together and one can conclude that 2012 is likely to see more low-level, but potentially tragically consequential attacks in malls, public spaces, and against iconic American targets at home and abroad.
Complacency about these trends is growing as memories of 9/11 fade, as America and its allies focus on seemingly more pressing economic and political challenges, and as Americans grow weary of the war on terror that began in Afghanistan almost a decade ago.