Government officials should avoid making vague statements about terrorism that have little empirical basis, said Alan Krueger, a professor of economics and public affairs at Princeton, at a Tuesday event at the Brookings Institution, a Washington nonprofit devoted to public policy research.
Krueger used as an example Homeland Security Secretary Michael Chertoff's July disclosure to the Chicago Tribune's editorial board that he had a "gut feeling" the country faced a heightened risk of terrorism during the summer. Chertoff said this feeling was based on past seasonal patterns of terrorist incidents, recent al Qaeda statements and intelligence he did not disclose.
Krueger, who served as the chief economist at the Labor Department from 1994 to 1995, said he decided to test that thesis with data on worldwide terrorist attacks from the National Counterterrorism Center, the federal agency responsible for compiling terrorism statistics. "I wouldn't draw too strong a gut feeling from this data," he said.
The economist found that, historically, attacks by al Qaeda and Sunni extremist groups have been no more frequent in the summer months. When all terrorist groups are counted, the number of attacks worldwide has been about 10 percent higher in July and August than in other months, he said. But he characterized this as a small difference, noting that other types of incidents such as boating accidents go up by much more than 10 percent in the summer.
"Would you scare 300 million people on the basis of those tiny blips in those charts?" Krueger asked. "It didn't seem to me to be constructive."
DHS spokesman Russ Knocke said Krueger's comments ignore the National Intelligence Estimate released in July, "which cites increased activity overseas as evidence of an enemy that is reconstituting."
"He may have also missed the news about the Glasgow plot, and the arrests in Germany and Denmark," Knocke said via e-mail, referring to an attempted car bombing at the Glasgow International Airport in July, and the arrests earlier this month of suspected Islamic terrorists by German and Danish authorities. "But, if any doubt lingers in his mind about activity in spring and summer months in recent years, he need only ask the families of victims from London, Madrid and 9/11."
Brookings hosted Tuesday's event as a discussion of separate findings in Krueger's new book, What Makes a Terrorist: Economics and the Roots of Terrorism. In it, the economist analyzed data from the NCTC and elsewhere, and came up with often counter-intuitive findings.
Most prominently, he found no evidence to support the notion that poverty and a lack of education breed terrorism. Although many terrorists come from impoverished parts of the world, on average terrorists are wealthier and better educated than their fellow citizens.
Individual studies had reached similar conclusions previously; Krueger's book collected comprehensive evidence.
Daniel Benjamin, a Brooking Institution senior fellow in foreign policy studies and a former National Security Council staff member, said terrorism scholars never believed the supposed link between terrorism and poverty or education. And Philip Gordon, another Brookings senior fellow in foreign policy studies and formerly the National Security Council's director for European affairs, said he thought it was obvious that poverty is not a significant cause of terrorism.
Gordon echoed the reasoning that Krueger used in the book. "If it were, we'd see terrorists teeming out of Chad, Haiti . . . and the poorest countries in the world," he said.
Still, the myth dies hard. One questioner heatedly pressed Krueger to explain his findings in light of the Gaza Strip, suggesting that an unemployment rate as high as 80 percent leaves the jobless susceptible to being recruited by terrorist organizations. Krueger said that over time, unemployment rates in the Gaza Strip and elsewhere have risen and fallen but the number of terrorist attacks has not changed accordingly.
"I guess I don't find it compelling to take one example and say unemployment is high and there's terrorism," Krueger said.
Gordon and Benjamin suggested that poverty could play an indirect role in causing terrorism, either by contributing to a sense of humiliation among inhabitants of poverty-stricken countries or by leading to more autocratic governments, a condition that seems to fuel terrorism.