Research suggests that the U.S. has historically made up a small portion of terrorist attack targets

One day has changed how Americans think about terrorism.

Sept. 11, 2001 was a day that certainly struck fear into the hearts of Americans and is a day that will be impossible to forget. However, recent research indicates that while the United States was the victim of a terrorist group on that fateful day, the U.S. is not a frequent target for terrorist attacks on U.S. soil or abroad.

Data in the 2009 study “Trajectories of Terrorism” points out that the 53 groups that the U.S. State Department consider special threats to the U.S. as a whole commit their acts of terrorism domestically. However, because of the magnitude of Sept. 11, the U.S. government has spent billions of dollars to prevent further attacks, according to researcher Dr. Gary LaFree, who runs the National Consortium for the Study of Terrorism and Responses to Terrorism at the University of Maryland.

“Sept. 11 is what some researchers would call a black swan," LaFree says. “It has had a huge impact on our thinking on terrorism. It has had a huge impact on policies, but what the data shows is that it is pretty darn unusual,” LaFree says.

The study looked at the 53 anti-U.S. groups acts of terrorism from 1970 until 2004. In total, the researchers analyzed 16,916 terrorist attacks that lead to 42,056 fatalities over the time span.

From this data, the researchers found that a little more than three percent of all anti-U.S. terrorist groups’ attacks that have occurred between 1970 and 2004 were directed at the U.S. At the same time, the U.S. also accounted for more than nine percent of fatalities related to terrorist attacks.

“We are spending a good amount of time and money and energy,” LaFree says. “We have adopted essentially a zero-tolerance mission. We’re spending billions of dollars to keep safe. Not everything being done has been effective, but if you look at it in its entirety, it’s definitely having an impact.”


There is a far greater tendency for domestic attacks within non-U.S. countries


The study also found that 90 percent anti-U.S. groups’ attacks occurred domestically and accounted for 84 percent of terrorism related fatalities.

Thus, the U.S.’ effort to root out terrorist groups greatly helps to save foreign, lives as well as American lives, according to LaFree.

“I think it ends up being the case that it is pretty difficult to pull of a transnational attack,” LaFree says. “Like crime, it is local. If terrorist groups have more resources, they would be militaries.”

The heavy concentration of terrorist attacks occurring within a group’s own country is very comparable to criminals perpetrating criminal acts against people who live nearby, according to LaFree.

“Terrorism is extremely territorial,” LaFree says. “It seems to happen locally.”

Terrorism has tended to affect countries around the world on cycles
The study also indicate that the amount of terrorist attacks both against U.S. targets and has cycled between periods of high annual numbers of attacks and low numbers three times over the data’s time span.

“A group finds a weakness and they exploit it until the home group reciprocates
and finds a way to counter it,” LaFree says.

The cycling between periods of a high volume of terrorist attacks and periods of relative inactivity are not accurately portrayed by the media, which has caused the findings of the study to surprise some readers, according to LaFree.

“You get the idea from the media that terrorism groups are always around and never disappear, but we find the opposite,” LaFree says. “...They are like business start-ups. They are often very short lived because it is not that easy to do.”

The results have also surprised readers given that the overwhelming majority of terrorist attacks are occurring domestically.

“I think when all people hear about this research they are surprised about how lopsided the attacks are in favor of domestic attacks,” LaFree says. “They aren’t even attacking U.S. targets in their own country.”

The U.S. has spent a significant amount of money during the time span of the study to prevent terrorist attacks which in part explains the low percentage of attacks against the U.S., according to LaFree.

The 1980s were the most active period for terrorist attacks

The researchers divided the groups included into the study into four trajectory groups. The 1980s boom accounted for 85.2 percent of the attacks on non-U.S. targets, while the 1970s onset only accounted for 9 percent.

However, the 1980s boom accounted for 56.5 percent of attacks directed at the U.S, while the 1970s onset accounted for 30 percent and the 21st-Century boom made up 5.1 percent. Of the groups that researcher placed in the 1980s boom trajectory, 57.1 percent of the groups were in both the U.S. and non-U.S trajectories.

The researchers consequently categorized the organizations not fitting into any of the waves as the sporadic group.

Researchers categorized 99 percent of the groups into their correct category, according to LaFree.

“Basically what this trajectory analysis does is takes ... each of the attack patterns of each group and asks the question ‘What’s the simplest way of combining these different attack patterns into broader categories,” LaFree says. “Once it gets to the end of categorizing them, it answers the question of ‘If you’re trying to put each of these groups into ...one of these four categories. How likely are you to be that you picked the right category?’...Essentially, instead of looking at 53 groups, we are looking at four broader groups.”

While there were the ratio between attacks against the U.S. and attack against other countries was above one in 1971, the ratio has not been above .20 at any point after the 1970s, according to the study. Between 1980 and 2004 the ratio between U.S. and non-U.S attacks has only reached 7.9 percent and above in 1993, 1998 and 2004., according to the study.

The bust cycles that are described in the study can also be explained by people growing tired of terrorism, according to LaFree.

“I think... people get tired of terrorism,“ LaFree says. “I mean, it is an incredibly divisive, destructive force... nobody is sad to see the end of the Tamil Tigers. So I think people essentially wear out.”