What is driving this? At the root is a special fear of Islamist terrorism, in particular, which is seen to be part of a large and hostile conspiracy that is international in scope.
The persistence of terrorism fears is surprising
The lingering anxiety about terrorism may seem surprising because, first, there has been nothing close to a repetition of 9/11. Indeed, scarcely any terrorist act before or after Sept. 11, either within or outside war zones, has created even one-tenth as much destruction.
In addition, the death toll in the United States from Islamist-linked terrorism has averaged six deaths per year since 2001. And an American’s yearly chance of being killed in the United States by a terrorist of any stripe stands at about 1 in 40 million for the period.
Moreover, official and media alarmism on the issue has declined over the years. We no longer see regular warnings from the government that an attack is imminent, for instance. And the U.S. government, in an effort to reassure the public, has increased its domestic counterterrorism spending by more than $1 trillion.
Yet 40 percent of Americans both in 2001 and today fear that they or a family member might become a victim of terrorism.
Our data also show that in 2013 and 2014 many Americans saw the country as less safe than before 9/11 — even more than had said so a decade earlier.
And the percentage who were confident (for the most part, only fairly so) that the government could protect them from such attacks has, if anything, waned over the decade and a half since 9/11.
Even the dramatic 2011 killing of 9/11’s chief architect, Osama bin Laden, lessened public fear for only a few weeks.
In the past, terrorism fears faded — but not after 9/11
This persistent post-9/11 fear does not stem primarily from a response to terrorism itself but, rather, from the international nature of Islamist terrorism. Two lines of evidence support this conclusion.
One involves data from the 1995 Oklahoma City bombing that resulted in 168 deaths. This was the second most destructive terrorist act ever in the United States and one of the worst in history. The perpetrator, Timothy McVeigh, set out to kill a large number of people and to do so essentially randomly — not unlike the mind-set behind al-Qaeda-backed terrorism.
Yet this alarming case of domestic terrorism did not lead to perpetual fear in the way Islamist terrorism has. Several poll questions go back to 1995, and reveal that Americans’ concern about terrorism declined considerably in the few years after the Oklahoma City bombing.
There’s a second comparison, as well. Many Americans during the Cold War had concerns about domestic communists. In many respects, fear of international Islamist terrorism is more like that inspired by U.S. communists than it is like that generated by domestic terrorists — people who, like McVeigh, are not linked to a foreign conspiracy or movement.
A few years after World War II, there was a growing sense of alarm about the threat presented by domestic communists — “enemies from within” who were seen to be connected to, and agents of, a vast foreign-based conspiracy to topple America. This fear peaked in the early 1950s and did not decline at all in the ensuing 10 years and only slowly thereafter.
The lingering concern about the internal communist danger is remarkable because media attention to that enemy fell nearly to zero in the 1960s and 1970s. This suggests that continual reminders about the threat are not needed for alarm to be sustained.
What does this mean for policymakers?
Politicians and the media are often accused of fearmongering on terrorism. However, the persistence of public fears even as media attention and official warnings fade suggests that they may be responding to the public’s fear of international Islamist terrorism as much as they are helping to create this fear.
Moreover, given the particular form of Islamist terrorism — led by what the public apparently sees as a hostile and nebulous international network — it may be exceptionally difficult to get Americans to believe that the threat has really been extinguished or at least that it is no longer significant.
However, this lingering fear suggests that policymakers have the freedom to spend counterterrorism money in a manner that best saves lives — rather than seek ways to reduce fears that may have become perpetual and are perhaps unfathomable.
John Mueller is a senior fellow at the Cato Institute and a political scientist at Ohio State University.
Mark G. Stewart is a professor and director of the Centre for Infrastructure Performance and Reliability at the University of Newcastle, New South Wales, Australia.
Together they are the authors of several books, including “Are We Safe Enough? Measuring and Assessing Aviation Security” (Elsevier, 2018).