Why hasn’t the U.S. witnessed another large-scale domestic terrorist attack since 9/11?
Whether navigating a busy New York subway or jumping between meetings on Capitol Hill, citizens and policymakers alike tend to take their physical security for granted. Eleven years removed from the devastating attacks of September 11, 2001, domestic security concerns have returned to a minor footnote as Americans go about their daily business. Recent discussions of U.S. defensive insulation from extremist militant violence largely center around protection for our diplomats abroad, not the U.S. homeland proper. However, it is important that we do not forget the collective sentiment of fear and uncertainty that swept the country following 9/11.
Isolated incidents including the foiled Times Square plot, the underwear bomber aboard Northwest Flight 253, and the Fort Hood attack reflect continuing terrorist threats, but on a much smaller scale than the loss-of-life from 9/11. Placing aside lone-wolf terrorism and violent sprees by criminals with no apparent allegiance to extremist ideals or organizations, what are the underlying reasons why terrorists have proven unwilling or unable to stage a large-scale coordinated attack upon the U.S. since 9/11?
The following graphic breaks down the reasons why terrorists have not succeeded in staging another 9/11-scale attack into two main categories: a) the reduction of terrorist capabilities and b) diminished motivations. Pertaining to the reduction of extremist capabilities, three factors reflecting the U.S. homeland security mission are central: 1) the physical “hardening” of infrastructure in a self-defense fashion, 2) the depletion of al Qaida leadership and financing, and 3) a vastly improved grasp of terrorist threats by the intelligence community.
In recent Congressional testimony, NCTC director Matthew Olsen stipulates that despite a reduction in core al Qaida’s capability to strike targets within the U.S., the group remains committed to direct attacks on Western targets over the long-run. Whereas American and NATO military operations have temporarily suppressed terrorist networks in Afghanistan, volatile political environments through the Middle East create great uncertainty over the role extremist organizations will play moving forward. If militant Islamic organizations are able to emerge from regional political struggles with considerable support and funding, it is plausible that they may shift operational focus back to their perceived Western enemies.
As American leaders contemplate an appropriate national reaction to the “second wave” of the Arab Spring, they would be wise to consider the question of why the U.S. hasn’t been victim of another large-scale attack. Are terrorists’ motivations to strike Western targets diminished, or only suspended due to the immediacy of more localized pursuits? Do reductions in capabilities lead to diminished motivations or vice-versa? In this chicken-or-egg argument, which way does the causal arrow actually run?
In terms of the U.S. homeland security response to terrorism, many important questions exist. The answers are not easily quantifiable, but they have real implications on federal budgets. Have expenditures to “harden” infrastructure really made Americans safer? Could terrorists circumvent these domestic defense systems with adequate training/financing/motivation?
The downstream effects of military operations are also extremely difficult to forecast. It is nearly impossible to determine whether the United States will be seen favorably in the Islamic world for our preferred narrative of “the triumphant victory of democracy over tyranny” or perceived as the meddling power who wore out a welcome it never received. Is the systematic rooting out of terrorist leaders through drone strikes and other operations enduring or only ephemeral? Will potential followers be dissuaded by a series of swift tactical defeats, or empowered by their martyrdom?
Lastly, what sort of handle does the intelligence community really have on contemporary threats to our nation? Have improvements in coordination and information sharing within the intelligence community thwarted major terrorist plots upon the homeland? Or, as some pundits suggest, are many terrorists simply inept and unfunded “wannabes”?
The future of homeland security and our collective defense against terrorism at home depends on the answers to these questions. The tendency toward overspending on worst-case scenarios must be balanced with the understandable expectation to never allow another 9/11 to happen. Of all functions of national governments in the Westphalian system, this one – our physical security within our own borders – is most fundamental.
