The second problem is the lack of a universal definition of terrorism. This makes correlating findings from one branch of study to another questionable. Many point to Schmidt and Jongman’s collation of 109 different definitions! Although large efforts are being made to build relevant databases one finds that even here the definitions of terrorism are not in agreement.
example, The Global Terrorism Database (GTD) holds over 800 incidents labeled
as ‘insurgent’ or ‘suspected insurgent’ while much research excludes such
incidents. There is an ongoing debate over whether or not to include state
sponsored terrorism in databases. Omitting Nigeria’s obvious indiscriminate
killing in its pursuit of Boko Haram members distorts the facts. [New
York Times, June 6, 2013] The Rand Database of Worldwide Terror Incidents
excludes state sponsored terrorism, although it has included them in the past. The
Department of Justice, naturally, seeks to include criminal behavior in its
analyses as did Crenshaw as she sought to include “organizational maintenance”
crimes. Just as naturally, governments try to ignore state sponsored terrorism for political reasons.
The third major problem is that of validating early data, gathering data, and correlating modern databases. Silke, Rutledge, and others have shown that most of the scientific research on terrorism began after 9/11, and the data that existed before then was mostly anecdotal. A handful of practitioners dominated the early work, mostly in non-collaborative fashion, and much later work was built on this weak, i.e. unsupported by data, foundation.
Related to this is the problem of defining ‘experts’. Talking heads of every stripe fill the media with their opinions, and write authoritative sounding books, and many are backed by no research at all. Post 9/11 research is much improved, but there also exists a plethora of methodological problems that hamper scientific analysis.
Crenshaw, M. (2000). The Psychology of Terrorism: An Agenda for
the 21st Century. Political Psychology, Vol. 21, No. 2. (Jun.,
2000), pp. 405-420.
Silke, A. (2008) RESEARCH ON TERRORISM: A Review of the
Impact of 9/11 and the Global War on Terrorism. School of
Law, University of East London, London, U.K.