What can be said about terrorism's strategic impact? Under what circumstances does it succeed or fail? Has it ever been a "driver" of historical change? These are just a few of the questions raised by the cases in this special issue of the journal. Nevertheless, they are daunting ones for the historian. Before answering them, therefore, it is essential to consider how the historian must apply the "tools of the trade" to this intractable problem.

The challenges that face the historian attempting to assess the historical significance of terrorism vary considerably, depending on whether the focus of the study is terrorism as a whole or a specific case study, as in this issue's articles. Some of these issues, such as the problem of defining terrorism, have been discussed, in part, by Bruce Hoffman earlier in the issue.[1]

If the focus is a single case study, then the primary challenge confronting the historian is the breadth of knowledge required to have a full understanding of the case. Indeed, the historian will have to draw upon skills and knowledge from a variety of academic disciplines, not simply those of history. Stuart Farson, for example, has identified a long list of knowledge issues that would be required to fully appreciate the complexities of the Khalistan Movement's attempt to establish a Sikh homeland in the Punjab. In his view, to understand this movement, one would need to know about:

Sikhism, Islam, and Hinduism; the history of the sub-continent; the socio-cultural, ethnic, religious-linguistic construction of the region; its economic geography; the politics of modern India, especially federal-state relations; the structure, policies, training, recruitment, and management systems of Indian policing; the nature of political violence in India and especially within the Punjab; India's international relations, especially with Pakistan, the US and China; and the nature, strategies and tactics employed in the "proxy war" between Pakistan and India; the equipment, tactics, cultures and strategies employed by India's and Pakistan's military; the structure, functions and activities of the Indian and Pakistani intelligence services, especially their use of disinformation, misinformation and propaganda; and the practices of the Indian and Pakistani governments, and of Sikh political and insurgent groups at home and abroad, in distorting and misrepresenting facts related to insurgencies in the Punjab and other areas.

He continues:

To these must be added: an understanding of the likely political and psychological outcome of genocide and other forms of mass murder; public expectations regarding civil liberties and human rights in India and what constitutes appropriate/inappropriate action; broad understanding of insurgency, terrorist, and separatist politics and counter-terrorist approaches; and last – but certainly not least – knowledge of the Punjabi language.[2]

Obviously, this list is specific to one case but the broader point is that the historian of a terrorist group or campaign needs to have expertise not only in history, but also in the domestic and international politics of the region and a range of socio-cultural, economic, and linguistic factors. Moreover, this expertise needs to extend not only to a specific group, but to the national and international counter-terrorism forces that may be arrayed against such an organization. Finally, the historian needs to be able to place the specific case in the wider context, not only of the region, but also of terrorism and counter-terrorism more broadly. The historian will have to rely not only on their own disciplinary skills, but will have to beg, borrow or steal tools, methods, and insights from other disciplines – psychology, sociology, political science, and international studies. History is inherently inter-disciplinary and the good historian must be a good poacher.[3]

While such analysis is likely to encompass some objective facts, it will also include subjective realities or narratives. History can be, and is, used for the purposes of political mobilization by both governments and terrorists, and by journalists and other observers to support particular lines of argument. The misuse or misunderstanding of history is an aspect of terrorism throughout time but specific historical narratives do not require deliberate manipulation to be effective for mobilization or justification of specific courses of action. They are constructed and the historian is ineluctably a part of this process. As an example, in the wake of the August 2006 plot to destroy multiple airliners over the Atlantic, several prominent Muslim leaders in Britain identified a link between increased Islamic radicalization in Britain and the country's foreign policy, especially in the Middle East, of supporting the „oppression' of Muslims. This assessment and overt linkage between terrorism and foreign policy was categorically rejected by the Blair government and by much of the mainstream British media, not only on normative grounds (even if opposition to government policy was a factor in radicalization, it could never justify the resort to terrorism), but also on factual ones. This latter point was best made by an editorial in the 13 August edition of The Observer, which argued that Muslim terrorism against United States long pre-dated the War on Terror and that much Western foreign policy in the 1990s had been dedicated to protecting Muslims from aggression, as in Bosnia or Kosovo, rather than perpetrating such attacks. The editorial ended by denouncing "bogus accounts of victimization."[4] This conveniently ignores the intrinsic subjectivity of such narratives and is historically selective since it also ignores the Muslim perception that ongoing Western support for Israel against the Palestinians and Israel's Arab neighbors, along with the presence of Western troops on the Saudi peninsula, dating back to the early 1990s, can be seen by Muslims as „oppression.' Whichever version of Western foreign policy is objectively more accurate, the narrative of victimization has considerable currency and carries significant weight as a radicalizing force in contemporary terrorism against such countries as the United States and Britain.

The pejorative nature of terrorism may also pose practical challenges for research since the scholar may require assistance from either specific groups that are either vehemently opposed to being classified as terrorists or even being part of a study of the phenomenon, or governmental sources that are insistent on such a perspective. The scholarly goals of objectivity and honesty are of vital importance here, but represent ideals to be strived toward rather than achieved, since perfect objectivity is unattainable. The problem is exacerbated by the secret nature of terrorism and counter-terrorism. Many terrorist groups and most governments provide substantial amounts of documentary evidence that the historian can use. For example, terrorists routinely produce material, such as communiqués, ideological statements, and training manuals. Such documents can be subjected to the same intellectual and academic scrutiny that applies to any historical source. However, to move beyond these documentary sources and the secondary literature, the scholar requires cooperation from those seeking to prevent terrorism or those who are actively engaged in it or have been so recently. Terrorism and counter-terrorism is a struggle not only over violence but also over legitimacy. Scholarly treatment offers a legitimizing force, especially for the terrorist, so cooperation (and thus justification for a group's actions) is often forthcoming but it would be rash to assume that a scholar perceived as sympathetic would not get more access to involved individuals than one perceived as unsympathetic. Likewise, the scholar must approach governmental sources with equal objectivity to avoid being misled or becoming simply a mouthpiece for government policy. Both terrorists and counter-terrorism forces – especially intelligence and security services – operate to a large degree in secrecy, so the historian must honestly acknowledge at the outset the limits of their knowledge and analysis.

The difficulties associated with objectively studying terrorism are real but they should not be over-stated. Good histories of both groups and the wider phenomenon exist and the challenges should not be permitted to become impossibilities. The extent of the problem faced by the historian in studying terrorism might be unusual but the fact of it is not. Historians need simply to treat the subject as they do others but with an awareness of the frequently emotive and subjective nature of the topic. They will do what historians have always done. They will start by trying to fill in the gaps in the record, for, notwithstanding the information overload of the Internet Age, there will still be blank spaces and black holes in the story. So, they will ask first: what is it that we still don't know? To answer that question, they will clamor for more documents and probe private papers. They will seek out and interview – if possible – the players on both sides. From these sources, they will identify and try to reconcile the differences between the public record, the secret one, the private one, and recovered memory. Where they can't be reconciled, the loose ends – the hangnails of history – will be left for other historians to ponder. History is never finally wrapped up neat and tidy. There always will be unanswered questions that will continue to fascinate historians and absorb their readers.[5]

What they will be unable to control, however, is how others will use the history they write. The Aum Shinrikyo case serves as an important reminder that policy makers and scholars have to be careful how they use case studies and history to inform thinking about countering terrorism. The Aum case was widely seen as a harbinger of future terrorism: a deadly and frightening combination of mass casualty technologies and apocalyptic beliefs. In fact, thus far it has been an „outlier': a unique event. But, it is one that shaped US counter-terrorism policy in misleading ways.

The Aum was a Japanese cult with mixed motivations, encompassing political, criminal, and religious elements, as well as some uniquely Japanese cultural elements. Its leadership held an apocalyptic vision focused on surviving in a post-Armageddon world. Shoko Asahara's charismatic leadership was rigorously enforced. At its peak the movement had 40,000 members, mostly in Russia. It had political aspirations; it contested the Diet elections in 1990 but failed badly. Consequently, Aum turned toward political violence. It feared the threat from the wider world, especially from the US, but Asahara's need to reinforce his status as a religious leader and other organizational factors played roles in Aum's shift toward terrorism and the specific timing of the March 1995 attack. However, the immediate catalyst for its Sarin gas attack on the Tokyo subway on 20 March was a police investigation of the cult. The attack was meant to disrupt the police effort.[6]

Aum had been experimenting with chemical and biological agents for some time, and had carried out a series of unsuccessful attacks prior to the Tokyo incident. Its efforts failed for several reasons: idiosyncratic leadership choices; rushed production; inability to get official help on key aspects of program; and the fact that the cult relied on second-rate scientists. So, how did it come to be seen as the harbinger of "the new terrorism"?

First, there was the unexpected nature of attack. Few had heard of Aum before March 1995, and its use of Sarin gas challenged traditional assumptions about terrorism: for example, that most cases involved low fatality incidents that were proportionate and instrumental in pursuit of limited strategic goals, such as national self-determination. The history of terrorism with non-conventional weapons had involved mostly small-scale acquisition, groups with more limited goals, such as the Rajneshee cult using Salmonella, or those who acquired dangerous substances but did not actually use them.[7] Aum was the first group with the potential to acquire non-conventional weapons that demonstrated its willingness to use them in an attempt to cause mass casualties.

Second, Aum's attack fitted the pattern of the time. Along with terrorism by the radical right in the US (notably the Oklahoma City bombing, one month after the Tokyo attack), attacks against US targets in Saudi Arabia and the rise of Palestinian suicide bus-bombings against Israel, Aum's attack seemed to indicate an evolution toward a "New Terrorism." New motivations, such as religion, non-traditional organizational structures, and an end to audience-driven proportionality seemed to suggest that terrorism was becoming less predictable and more lethal. The combination of Aum's attack and the Oklahoma City bombing were especially important in highlighting the threat within the US and the possibility that terrorists might use weapons of mass destruction (WMD).

Aum's attack appeared to raise the bar by creating a new model for others to follow. It was self-sufficient, had no state sponsorship, and engaged in multi-track micro-proliferation. It was successful in promoting chemical, biological, radiological, and nuclear (CBRN) weapons as a means to gain attention. But these concerns obscured the facts that Aum's effort was not followed by a wave of similar groups or attacks. Moreover, the few fatalities from Aum's attack (12 in all) showed how hard it is to kill many with CBRN. But that lesson was imperfectly learned until years later; it was a source of academic and policy debate through much of later 1990s.

Arising from that debate was a conflation of WMD and CBRN by both American policy makers and scholars. Likewise, they shared the belief that major future attacks on the US would involve CBRN weapons, not conventional weapons or their derivatives. This decision resulted in a massive effort to prepare the US for CBRN attacks through the Domestic Preparedness Program (DPP). Billions of dollars were spent to prepare cities, first responders, and multiple agencies and jurisdictions.[8] This decision was partly understandable. As former White House Counter-terrorism coordinator Richard Clarke explained: "[in 1996] we had no capability to deal with a CBW being used in the US."[9]

Tim Naftali, author of Blind Spot (the history of US counter-terrorism efforts written for the 9/11 Commission) suggests that the US focus on CBRN weapons dating from Aum’s attack may have contributed to the "failure of imagination" identified by the commission. The 1993 World Trade Center attack had shown the vulnerability of major buildings. Post-Oklahoma City, some efforts were made to identify vulnerable facilities, especially US installations overseas but it was a Herculean task due to the large number of potential targets, and the assumption remained that casualties would be in the hundreds, not thousands. This assessment was reinforced by the attacks on US facilities in Saudi Arabia, the 1998 African embassy bombings, and the 2000 attack on the USS Cole. The US counter-terrorism community did not rethink their strategic assumptions that al-Qaeda was far from developing WMD, so would be unable to kill thousands in the foreseeable future. The DPP was not primarily intended to be a response to massive conventional weapons. Even the Millennium plots of December 1999 did little to overturn the conventional wisdom on the domestic threat.[10]

This "group think" was not unique to the policy community. It was also reflected in the scholarly literature. Compared to the vast attention the group would receive after 9/11 there were relatively few articles on al-Qaeda prior to 2001. However, there were many scholarly articles and even more media pieces on WMD terrorism, all discussing CBRN weapons.[11] Walter Laqueur argued that "In retrospect, most terrorism experts did not pay sufficient attention to the bin Laden conspiracy which, after all, had been many years in the making and affected many countries on all continents."[12] He attributed this failure to a variety of causes, including a fixation on the impending use of WMD, driven by the Aum case. As time passed and Aum's attack was not replicated by other groups, some of the tenets of the "new terrorism" debate (of which mass casualty attacks were a part) were increasingly questioned. But massive conventional attacks simply were not considered adequately.[13] Moreover, much of the scholarly work on the Aum misunderstood the case. Milton Leitenberg showed that, even after contradictory evidence became available, for several years scholars continued to rely on, and failed to challenge, key early studies of Aum's attempts to acquire biological weapons, resulting in what he called "serial propagation of misinformation."[14] His point has wider relevance. As much of the evidence for terrorism is difficult to acquire (always beforehand and often in retrospect), many of the assessments in the literature are made on the basis of limited hard evidence and may consequently be incorrect in detail and sometimes even in substance. Aum was an important case in its own right but not as a model. Nor was it a seminal event.

How, then, will 9/11 be seen by historians? Was it the seminal event of our age, as it appeared at the time, or a major terrorist incident but one, like the Aum's attack, that seems less historically or strategically significant in retrospect than when it occurred? The ripple effects of 9/11 were felt around the globe in real time and even now it is hard to escape the sense that this was a world-shaking, world-shaping, watershed event, one that will forever mark a boundary between the world we knew before 9/11 and the one we lived in after. David Charters grapples with these issues in his article.[15]

It is unlikely that many of the basic facts will be in dispute. Thanks to prolific and persistent journalists, dedicated scholars, a commission of inquiry, and even the records left by the perpetrators and their mentors, we already have a pretty good chronology of events, from the creation of al-Qaeda, through the planning stages and preparations, to the launching of the attacks. We know quite a lot about the key actors. We also know a great deal about the sequence of events that followed in the United States, among its allies, and in other countries touched by the attacks: Afghanistan, Iraq, Indonesia, and central Asia. More information enters the public domain daily and more will come in the decades that follow as once-secret archives are opened, at least partly. Interviews with participants, trial records, and memoirs will be added to the record. The future historian of 9/11 will not suffer from a paucity of information but from a surfeit.

If they are true to form, future historians will debate endlessly, the "why" questions. These, more than anything else, will be what sustains the process of historical inquiry, what continues to breathe life into events long after their participants and firsthand observers have passed on. Why did bin Laden decide to declare war on the West? Was he outraged to the point of rebellion by the stationing of Western forces in his country? Or was it really all about the Palestinians and the Israelis? Was it because his religious beliefs or his religious mentors persuaded him that there was no other course? Was he truly offended by what he saw as corruption in Saudi – and by extension – Muslim society? So, was 9/11 really a battle in a larger struggle over the fate of Islam? Or was bin Laden caught up in what Bruce Hoffman has called the cult of the insurgent? What was the history he learned, what "lessons" did he take from it, and how did he apply them? Was the Afghan War the Jihadists equivalent of the battle of Karameh? Did he have an achievable end-state in mind and clear plan of how to get from start to finish? Why were so many others, and yet – in the context of the whole Muslim community – also so few, inspired to follow his lead? What motivated young Muslim men to abandon productive lives and sacrifice themselves for his cause?

Long after the 9/11 Commission report is gathering dust on library shelves, historians will still ask, "How could this happen to the United States, the pre-eminent superpower of its day?" Why did they fail to see the warning signs? Why did they not act sooner? Was it solely an intelligence failure? A policy failure? A failure of "imagination" as the 9/11 Commission suggested? Was it a "conspiracy" by dark forces with hidden agendas? Or was it simply gross incompetence – a symbol, symptom, and signal of the national malaise that inevitably precedes and accompanies imperial decline? Historians will – quite rightly – explore the impacts of American foreign policy in the region and its unintended, unanticipated consequences. Will they conclude that America itself is to blame, a victim of "blowback," the author of its own fate? And in responding to the attacks, did it walk into yet another "terrorist trap" with „eyes wide shut'? If so, why?

All the while they will have to ask those questions in the context of what was known and what was happening before the attacks occurred. Events don't happen in isolation but are sketched upon a larger canvas already colored by other events, personalities, trends, policies, and actions, a range of influences that don't always produce predictable or logical outcomes.[16] And when they turn to the question of 9/11's significance, historians will have to tread more carefully, for the clues here are often more subtle, all the more so for seeming obvious. 9/11 may indeed ultimately prove to be an artificial dividing line, but to prove or disprove its legitimacy as a "turning point," historians will have to ask: "What was truly new and different after?" Thus they will need to look for continuities and discontinuities.[17]

The Aum case suggests that we need to be wary of drawing lessons for future acts of terrorism, especially if we try to base substantial analytical or policy changes on a single case. It also offers an excellent justification for taking a long-term view of specific terrorist campaigns or incidents and this is obviously the historian's stock-in-trade. It is all too easy to reach rapid conclusions about the significance of an incident: the imperative for a policy response is immediate, in order to protect lives and property; criminal cases may need to be constructed; much discussion will often be found in the media and, frequently, it is scholars who are called upon to offer their expertise. All of this puts a priority on a rapid judgment on the importance and wider significance of a group or incident but is less effective in providing thoughtful analysis. Historical perspectives on such events offer an important corrective to these inclinations and have the advantage of temporal (and often some degree of emotional) distance from the immediate situation. It is in providing such mature reflection that the historian's role in studying terrorism is paramount.

Mark Sedgwick and David Rapoport, with their separate typologies but united concept of "waves" of terrorism, suggest that a key strategic impact of such violence is its ability to inspire other groups to adopt similar tactics. Bruce Hoffman makes a similar point in this issue in his discussion of the „cult of the guerrilla.' Those who seek to emulate previous groups or campaigns probably do not study them critically. They may be encouraged by the rare success rather than being cautioned by the much larger record of failed or inconclusive campaigns.

As suggested in the Introduction, not all terrorist campaigns are equal in terms of strategic impact. The impacts of the cases included in this issue break down into three broad categories: global, regional, and minimal. The assassination of Archduke Franz Ferdinand, the Nazi terrorist campaign to weaken the Weimar state, and al-Qaeda's campaign and the American and allied response clearly fit under the global category, because their effects resonated on a scale that affected and shaped the strategic policies, actions, and futures of major powers and had consequences that spanned the globe. The four national liberation terrorist campaigns (Irish, Jewish, Algerian, and Palestinian) changed regional politics in a significant way. Since they have drawn in major powers, the Jewish and Palestinian campaigns straddle the boundary between regional and global impacts but their significance has been primarily regional. Finally, not every terrorist campaign ends in victory. The French Rightists failed to take power in the 1930s, although their violence and threats contributed to the collapse of the government. Apart from refocusing attention on what has been called the 20th century's first genocide, Armenian terrorism's strategic impact was practically nil. The terrorist campaign of the Revolutionary Organization 17 November was anachronistic, incoherent, and doomed to failure from its very inception.

In fact, John Mueller argues that, by itself, sub-state terrorism rarely has had a significant historical impact. He asserts that any historically significant developments that emerge from terrorism generally derive not from the act itself but from the reactions or overreactions of states and electorates to that act.[18] This, of course, may be true but it begs a larger question: would those reactions or overreactions have occurred without the galvanizing event? If not, then it may be misleading to downplay the significance of the terrorist actions that prompted the response.

But Mueller makes two exceptions to his own argument: assassinations and cases where the targeted state has a low threshold of tolerance for sustaining casualties. Not all assassinations are terrorist acts but a few that were part of terrorist campaigns have had a notable strategic impact. For a terrorist assassination to be historically significant, it must exert a major impact in a wider context. The murder of the Archduke Franz Ferdinand is a case in point. As Keith Wilson points out, the archduke's assassins did not set out to ignite the First World War but their actions created a crisis – and a pretext – that was exploited by the Austrian government to impose policies they intended to carry out anyway, leading inexorably to a major conflagration that re-shaped Europe.[19]

If the terrorists' target has a low tolerance for casualties, even relatively small acts of terrorism can alter its policy. Zionist terrorism may have been influential in convincing the British to leave Palestine in 1947, although the asymmetry of will between the two sides was an important element in the process. The British government's low tolerance for casualties occurred in a conflict it came to regard as unimportant, especially given the war-weariness of the country and in light of a reassessment of its strategic priorities once the Indian sub-continent – the centerpiece of the empire – achieved independence.[20]

Equally, American forces sent to Lebanon in 1982 and Somalia in 1992 were engaging in peacekeeping missions that few Americans considered to be worth very many lives. Thus, when terrorist bombs in the first case, or a wild firefight in the second, took the lives of a significant number of those forces, American attitudes and policy shifted and the troops were withdrawn. These two examples are significant because they are frequently cited by bin Laden as proof that because of their reluctance to tolerate casualties, the West and the United States in particular is vulnerable to defeat abroad by a dedicated campaign of terrorism. Clearly, the inspirational value of such cases gives them heightened historical significance.

Sometimes these reactions are self-defeating or even self-destructive acts of counter-terrorism that play into the hands of the terrorists, as was the case of France in Algeria. States often overreact to terrorist events simply out of rage, fear, or a desire to exact revenge; they lash out impetuously at the perceived threat with little careful analysis, partly because it represents an immediate, emotionally satisfying, and often popular action against those groups or individuals that have attacked the state. However, the historical significance again arises from the reaction, not from the terrorist act itself. In 1986, President Reagan ordered the bombing of Libyan targets with planes launched from Britain. The attacks were intended to "send a message" about Libyan sponsorship of terrorism and, more immediately, were a reprisal for the bombing of a Berlin discotheque that killed two people, one of them American. The short-term gain for the United States was limited and the long-term impact was detrimental. Two years later, Libyan agents participated in the bombing of Pan Am flight103 over Scotland (thus simultaneously targeting both the United States and Britain) that killed 270, of whom 187 were Americans and forced Pan Am into bankruptcy.[21] Likewise, when al-Qaeda bombed two American embassies in Africa in 1998, killing 224 people and injuring several thousand, President Clinton retaliated by bombing some of bin Laden's terrorist training camps in Afghanistan. This caused the Afghan government, the Taliban, to reverse their previous undertakings to extradite bin Laden to Saudi Arabia. Al-Qaeda became a magnet for funds and recruits, and was cemented as the pre-eminent Islamic oppositional group to US global hegemony. The Taliban moved from being reluctant hosts, fearing the destabilizing impact al-Qaeda was having on their regime, to being allies and partners.[22]

Similarly, the Indian government massively overreacted to Sikh terrorism in 1984 by attacking the Sikh's holiest place, the Golden Temple in Amritsar. The attack on the temple killed the key Sikh fundamentalist leader, Bhindranwale, along with hundreds of others. This resulted in an escalation in violence: the assassination of Prime Minister Indira Gandhi by her Sikh bodyguards, which in turn resulted in the Delhi riots in which up to 4,000 Sikhs were killed in three days. Furthermore, the 1985 destruction of an Air India plane in which 329 persons perished, the largest death total caused by a terrorist attack until 9/11, can also be seen as a direct result of the attack on the Golden Temple.

By the late 1980s, the Indian government had further stiffened its counterinsurgency policies, and provided the police with new powers, better training, and modern weapons. In this new situation, the police adopted a strategy of searching out and confronting the leadership of insurgent groups and their supporters. Police termed these confrontations as "encounters." Quite frequently all of the insurgents ended up dead and their bodies were quickly cremated, while the police did not appear to have suffered any casualties. One of those killed in these circumstances was Talwinder Singh Parmar, the fundamentalist and charismatic head of the Babbar Khalsa in Canada and the prime suspect in the destruction of Air India flight 182. However, contrary to other examples here, police actions against Sikh "extremists" in India ultimately played an important role in the decline of support for Khalistan, even if the shorter-term impact was a substantial escalation in the violence. Farson cites the figure of 11,694 people killed in India by terrorists between 1981 and 1993 (of which 61 percent were Sikhs), and some 20,000 by police in the late 1980s and early 1990s.[23] Today, the Khalistan movement is dormant.

Electorates also sometimes respond to terrorism in counter-productive ways. Between 1996 and 2001, Palestinian militants apparently used terrorism inside Israel to sabotage Israeli-Palestinian peace talks. Israeli voters elected to office parties and prime ministers (Likud leaders Benjamin Netanyahu and Ariel Sharon, respectively) who, like the terrorists, were hostile to the negotiations. The train bombings in Madrid, Spain in March 2004 are thought to have been significant because the attacks were almost immediately followed by the election of a party committed to withdrawing Spanish troops from the war in Iraq. However, the Aznar government was widely seen to have mishandled the immediate aftermath of the attacks, blaming the Basque group, ETA, for the bombings. It was more likely that the electorate was responding to this mismanagement, than to the terrorist attacks. Moreover, the incoming socialist government was fulfilling an election pledge to withdraw Spain's troops from Iraq made before the attacks occurred. However, it may be equally significant that al-Qaeda had analyzed the political situation in Spain and concluded that support for the war was weak and that the government was vulnerable to pressure by violence. Whatever the reason, the consequence was a victory for the terrorists.[24]

Another common reaction to terrorism is to become overly-protective and to overspend on security. Sometimes, target countries can become so fearful and self-protective that significant consequences, particularly economic ones, ensue. The costs of reaction to 9/11 in the United States outweigh those imposed by the attacks, which were by far the most destructive in history. The direct economic losses of 9/11 amounted to tens of billions of dollars but the economic costs in the United States of the enhanced security runs several times that and the consequent disruption escalated the cost: Robert Congleton argued that the effective need for people to spend an additional half-hour in airports cost the American economy US$15 billion per year.[25] The reaction to the anthrax attacks cost the United States Post Office alone some five billion dollars: one billion for every fatality inflicted by the terrorist.[26]

In addition, there have been substantial opportunity costs: the enormous sums of money being spent to deal with the threat of terrorism have in part been diverted from other activities. Not all money spent on countering terrorism is without wider benefits. However, the money does come from other programs that are important yet consequently under-funded. Unquestionably, severe funding distortions have occurred, even within agencies: almost 75 percent of the appropriations for first responders went for terrorism rather than for natural disasters, and US$2 billion was made available in grants to improve preparedness for terrorism but only US$180 million for natural disasters, such as Hurricane Katrina.[27] In the 1990s, a similar effect could be seen in the funding directed toward first responders' ability to cope with incidents involving chemical, biological, radiological, or nuclear materials in the United States. Arguably, this came at the expense of preparedness for a range of other types of incidents.

If the war in Iraq is seen as part of the War on Terrorism, then the reaction to 9/11 also has claimed more human lives than were lost in the terrorist attacks. The number of Americans, military and civilian contractors employed by the Department of Defense, who have died thus far in the conflict in Iraq exceeds the number killed on September 11. More than 20,000 have been wounded. This excludes those killed or wounded in Afghanistan and all those working for other departments and agencies, or, obviously, for other countries.[28] Moreover, the war in Iraq probably resulted in the deaths of 100,000 Iraqis during its first 18 months alone.[29] This could represent more fatalities than were inflicted by all sub-state terrorism, domestic and international, over the last century.

Although it is impossible to prevent every terrorist act, robust states, especially democracies, are not "vulnerable" in the sense that they can be toppled by dramatic acts of terrorist destruction, even extreme ones. This is a lesson that could have been learned from the example of the Anarchists in the late nineteenth and early twentieth centuries. Although they succeeded in killing an impressive array of heads of state and leaders of government, and in spite of being armed with a newly destructive weapon, dynamite, that contemporaries believed would bring societies to collapse, the Anarchists were unable to exact meaningful change. Societal and civic structures were more effective at surviving bombings than physical structures or political leaders. Terrorism can bring about major, possibly even strategic changes that would be of great historic significance, but short of a cataclysmic event it would be the responders, not the terrorists, who would bring it about. Ultimately, the enemy, it appears, is us. Terrorists very often hope for, indeed rely upon, overreaction by their foes. This goal of sparking an overreaction seems central to bin Laden's strategy, as to that of many other terrorists.' Bin Laden seeks to bleed "America to the point of bankruptcy," and depends upon inadvertent cooperation from his target, noting that the 9/11 terrorist attacks cost al-Qaeda US$500,000 while the attack and its aftermath inflicted, he claims, a cost of more than US$500 billion on the United States.[30]

In spite of the apparent political imperative that public officials "do something" to respond to acts of terrorism, leaders can restrain their instinct to overreact and such a limited reaction is politically feasible. In contrast to the Reagan administration's reaction to Libya two years before, in response to the bombing of Pan Am 103 the Bush and Clinton administrations sought compensation for the victims, and applied police, diplomatic, and intelligence efforts to prosecute those responsible. This approach took years to yield results but was politically acceptable. Thus, despite short-term demands that some sort of action must be taken, politicians can often successfully ride out this demand after the obligatory expressions of outrage are prominently and promptly issued.

It is worth noting, however, that under-reaction, though less common, can also be a problem. The sabotage of Air India Flight 182 on 23 June 1985 using an improvised explosive device (IED) constituted the most deadly mass murder in Canadian history, claiming 329 victims, the vast majority of whom were Canadian citizens of Indian extraction. It could have served as a watershed event for Canadian counter-terrorism but it did not. The inability to obtain convictions after a prolonged investigation represents a multi-leveled failure of government, police, and intelligence. This is no less the case than if the government had over-reacted, since proportionality is critical in both an assessment of terrorism's strategic impact and in the correct response to a terrorist campaign.[31]

This brings the discussion back to the role of history in the study of terrorism. Objective, scholarly analysis is not only possible but is inherently valuable in its own right for its own purpose: the dissemination of knowledge. But it is equally important from a policy perspective, in order to see the world through the terrorists' eyes, to more fully understand a campaign and, thus to avoid doing the very things that will help them achieve their objectives.