Not long after September 11, an Al Qaeda strategist called Abu Bakr Naji wrote that the greatest effect of the attack was that it had punctured what he called the United States' "deceptive media halo". Naji felt that Al Qaeda's strike, which murdered about 3,000 people, had destroyed a widely held perception that the United States was so powerful that it was not even worth attacking. For Naji, September 11 was about revealing the United States as a paper tiger.
No doubt he had a point: even in the United States civilians are vulnerable to concerted efforts by terrorists to kill en masse. But in the years since September 11 it is not the United States that looks like a paper tiger, but Al Qaeda. Since 2001, 17 Americans have been killed inside the United States from Al Qaeda-related terrorism, which has failed to achieve any of its key goals. The United States is still a major player in the Middle East, Israel still exists and regime change in the Middle East has ushered in democracy movements rather than jihadi-inspired governments.
Al Qaeda has had some notable operational successes attacking western European countries, but its general inability for sustained attacks has led the group to turn its violence against Muslims in Middle East. Al Qaeda in Iraq was particularly brutal in its attacks against both Shiite and Sunni Muslims. Researchers at West Point's Combating Terrorism Center found that 84 per cent of Al Qaeda's victims between 2004 and 2008 were Muslim.
The violence against Muslims is important because it illuminates Al Qaeda's general inability to establish a broad political support structure. After September 11, many in the United States held the erroneous belief that Al Qaeda's virulence might inspire mass movements in the Middle East and elsewhere. Al Qaeda no doubt hoped to be a vanguard that would inspire a following, but that aspiration proved to be a mirage.
Al Qaeda remains virulent and dangerous, but it is fundamentally a fringe group intent on "purifying" the practice of Islam. What that means is that Al Qaeda's war is fundamentally against other Muslims as well as the United States. Nonetheless, a number of US policy responses to September 11, including the counterproductive invasion of Iraq, were motivated by the fear that Al Qaeda would become a mass movement.
But the understanding of Al Qaeda has grown more nuanced over the past decade, even as US counterterrorism efforts have substantially weakened its core leadership in Pakistan and its affiliates. Indeed, Al Qaeda has been compelled to increasingly to focus on propaganda designed to radicalise people from afar because the group has lost the capability to conduct training camps.
It is not quite right to say that the threat has decreased since September 11, although the odds of another attack on the scale of September 11 are lower as a result of pressure on Al Qaeda-linked organisations around the globe. The reason is that the presence of US troops in Afghanistan and Iraq - and operations in Yemen and Somalia - offer Al Qaeda prime talking points for recruiting even as they limit the ability to organise large-scale strikes. While this trade-off makes sense from a US perspective, it is hard to imagine defeating Al Qaeda's ideas while US troops are in Iraq and Afghanistan.
Indeed, Al Qaeda has reached a point of stasis where it is unable to achieve its goals but is nonetheless quite resilient. The group has sustained itself and continues to attract recruits despite its inability to actually generate political change.
Al Qaeda's failure to achieve any of its key political goals stands in stark contrast to the protesters and revolutionaries who have stepped to the forefront of world events during the Arab Spring. Not only have those visionaries actually upended long-entrenched dictatorships; in many cases they did it peacefully. Although Al Qaeda's leadership has hopes of using the current instability to attract recruits, the group has had to square its legacy of failure with the dramatic victories of tech-savvy democracy activists.
Ten years after September 11, Al Qaeda is not nearly as terrifying as it was in the days after that awful event. The deceptive media halo it created for itself by destroying the World Trade Center has been eroded by repeated failures and the backlash caused by the deliberate targeting of innocent people.
Despite political failures, Al Qaeda continues to thrive as a fringe group preying on a small population disillusioned by the interconnected modern world. Most dangerously, these ideas are increasingly prominent among the constellation of terrorist groups originally sponsored by Pakistan. In Yemen, adherents rally around tribal grievances and threaten not only the West but key financial and economic centres in Saudi Arabia and elsewhere in the Gulf. In Egypt's Sinai peninsula, a smattering of insurgents espousing Al Qaeda's ideology is attempting to disrupt relations between Israel and Egypt, which might destabilise the region if they succeed. In the West, individuals conduct one-off attacks inspired by Al Qaeda propagandists.
Al Qaeda's future is likely to be long, but not particularly bright. Like many extremists, Al Qaeda's vision is failing - the key questions now are how many people they will kill on the way to the dustbin of history, and whether the world can effectively scale its response to them. Ten years after September 11, we better understand the problem Al Qaeda poses, but we still do not have all the solutions.
Brian Fishman is a counterterrorism research fellow at the New America Foundation. Follow him on Twitter at @brianfishman