Is the US on the correct anti-terrorist course - Part II

That the most vivid and recent terrorist attacks on the US were executed by hijacking, coupled with the fact that aviation security has attracted more resources than other threats, suggests that US policymakers might be subject to risk misperception. Because 11 September 2001 comes most easily to mind, policy experts may be overestimating the probability of attack using aircraft as opposed to other methods — such as water contamination — and acting accordingly. In addition, because 11 September was such a horrific incident, associated emotions may be persuading policymakers to ignore probabilities and reduce the likelihood of a similar attack, whatever the cost.

However, the range of measures that have been implemented within the area of aviation security point to a different explanation for this apparent misallocation of resources, since they aim to reassure as well as protect the public — the two are not always synonymous. The prioritisation of highly visible policies over ‘behind the scenes’ measures indicates that, in its excessive attention to aviation security, the US government is responding to the public’s misperception of risk rather than its own interpretation. Threats to aviation security can come from passengers, airline and airport personnel or in hold baggage or air cargo. The security measures most visible to the public are those affecting passengers and their luggage; these are the two areas in which security has been most dramatically increased.

The newly created Transport Security Administration (TSA) has replaced private contractors at airport screening with 55,000 better trained and better paid federal employees. Since December 2002 it has achieved 100% baggage screening. A new computerised passenger screening system will soon check identities and assess potential risk, while a planned Registered Traveller program will be able to recognise passengers who have already submitted to extensive background checks. There have also been great efforts to improve physical security on the aircraft themselves, including the deployment of air marshals, fortified cockpit doors and a programme to arm pilots. All these measures are highly visible and well reported to the general public.

‘Behind the scenes’ measures have received less government attention. For example, initial background checks on personnel at just two US airports failed to disqualify dozens of workers with criminal records. The TSA has taken no steps to physically screen employees and there are no standard procedures for employees’ access points to secure areas. The upcoming Transportation Worker Identification Credential programme has not been accorded the same importance as those that aim to improve passenger security. Furthermore, almost no measures have been taken to reduce the security threat from unscreened freight that travels as hold cargo in passenger aircraft.

The Department of Transportation’s inspector general found in 2002 that the existing programme of Known Shipper lists could be "easily circumvented" by terrorists seeking to place explosives on an aircraft; an internal TSA document said that "cargo is… the primary threat vector". However, in June 2003 the then Department of Homeland Security Assistant Secretary for Information Analysis testified that he has "not considered" the potential threat from unscreened passenger airline cargo. Were the US response to the terrorist threat wholly rational, neither visible nor behind the scenes measures would be any more likely to attract resources.

Overallocation of resources to aviation security

This bias towards more visible security measures suggests that an overallocation of resources to aviation security must at least partly be explained as a government attempt to reassure the general public, arising from a belief that the public overestimates the threat posed by aviation. It is too difficult to tell the extent to which the US government also overestimates the threat. Although this article cannot investigate all aspects of America’s implementation of its homeland security strategy, it is reasonable to expect that other areas of anti-terrorist policy show similar patterns of reassurance as well as protection. However, they are unlikely to be as marked as aviation security, because of the association of aircraft with 11 September.

What policy recommendations can be drawn from this conclusion? Firm in the belief of the ultimate rationality of consumers, The Economist would argue against policies of reassurance where they are not the most efficient way of reducing the terrorist threat to life and property.

However, sociologists such as Bigo argue that reducing fear, even if it stems from an irrational base, is a task of government. Slovic points out that due the emotive nature of the threat, the public is unlikely to be reassured by simply emphasising the low-probability nature of the terrorism. This leads to the conclusion that a response to terrorism which is not the most efficient way to reduce the threat of terrorism may be justified — if it reduces the public’s fear.

Problems in methodology

These conclusions require further qualifications concerning the limitations of the method of analysis used in this study (see also RJHM March 2004, pp7-9). First, the decision-making process has been oversimplified. For example, overattention to aviation security may be due to a distinction between acts of omission and acts of commission, not misperception of risk. A government would expect greater political repercussions from a failure to respond to a previously experienced source of danger than from a known but not experienced threat. Additionally, the complicated reasoning behind the international aspect of US counter-terrorism measures means that it is not easy to assess whether the National Strategy for Combating Terrorism is subject to risk misperception.

Second, an analysis using probabilities is only really useful when dealing with random events such as natural disasters. Terrorism involves terrorists (agents) who respond to governments’ policies (or inaction) and would therefore be better modelled by game theory. Governments may choose to follow apparently inefficient policies to signal their serious intent to the terrorists and discourage them from acting.

Finally, and perhaps most importantly, this analysis fails to distinguish between risk and uncertainty. Throughout the article it has been assumed that it is possible to determine probabilities of attack (risks). This may not always be the case. Under conditions of uncertainty, where probabilities cannot be assigned, it is reasonable to follow the maxim in principle — in other words, pursue "the option that has the least bad outcome". For example, it may be sensible to devote extremely large resources to prevent an attack similar to those of 11 September, because the actual probability of it happening is not known for sure. This has particular pertinence to extremely catastrophic outcomes, such as the defeat of the country. Since the US considers terrorism a threat to its national security as well as the security of its individual citizens, it is perhaps to be expected that they devote more resources to reducing the threat than would be expected if one considers the threat to life and property alone.

We must conclude that although this article’s analysis of the US response to the events of 11 September has shown up some interesting areas of ‘irrational’ resource allocation that can be explained by misperception of risk, the tools used in the assessment are relatively crude. Further investigation into the decision-making process of policymakers and implementers is required to be sure that these allocations cannot be explained differently.

Amy Leyland is an analyst with The Terrorism Intelligence Centre in Canberra, Australia


1 In a world of perfectly rational and perfectly informed people, policies that reassure would be those that protect and vice versa. However, something that reduces the threat of terrorism will not necessarily reassure the public (for example, if they are not aware of it or do not trust the government’s analysis). Similarly, something that reassures the public may do nothing to reduce the threat it faces.

2 Sara Kehaulani, ‘Airport Finds That More Screeners are Questionable’, The Washington Post 12 June 2003.

3 ‘America at Risk: A Homeland Security Report Card’, July 2003, The Progressive Policy Institute, Washington, DC,, p18.

4 The attention given to the security of nuclear power plants over nuclear material is a case in point. Although power plants have always had a high level of security, and worst-case scenarios of terrorist attacks on plants or nuclear waste under transport indicate a very low likelihood of collateral injury, since 11 September 2001 the industry has spent nearly US$400 million on additional security to meet new regulations from the Nuclear Regulatory Commission. However, the security of general nuclear material, such as what would be suitable to make a dirty bomb, remains very low; there are approximately 250 reports of lost or stolen material each year.

5 Didier Bigo, ‘To Reassure and Protect, After September 11’, Social Science Research Council,

6 Paul Slovic and Elke U Weber, ‘Perception of Risk Posed by Extreme Events’, paper prepared for discussion at the conference ‘Risk Management Strategies in an Uncertain World’, Palisades, New York, 12-13 April 2002, p4.

7 Cass R Sunstein, ‘Terrorism and Probability Neglect’, The Journal of Risk and Uncertainty, Vol 26 No 2/3, p129 (2003).


Explore our related content