Gwern has an amazing essay on this: http://www.gwern.net/Terrorism%20is%20not%20about%20Terror http://www.gwern.net/Terrorism%20is%20not%20about%20Terror And

Gwern has an amazing essay on this: http://www.gwern.net/Terrorism%20is%20not%20about%20Terror http://www.gwern.net/Terrorism%20is%20not%20about%20Terror And also: http://www.gwern.net/Terrorism%20is%20not%20Effective http://www.gwern.net/Terrorism%20is%20not%20Effective >In a [previous study of mine] assessing terrorism’s coercive effectiveness, I found that in a sample of 28 well-known terrorist campaigns, the terrorist organizations accomplished their stated policy goals 0% of the time by attacking civilians. >Jones and Libicki (2008) then examined a larger sample, the universe of known terrorist groups between 1968 and 2006. Of the 648 groups identified in the RAND-MIPT Terrorism Incident database, only 4% obtained their strategic demands. More recently, Cronin (2009) has reexamined the success rate of these groups, confirming that less than 5% prevailed…Chenoweth and Stephan (2008, 2011) provide additional empirical evidence that meting out pain hurts non-state actors at the bargaining table. Their studies compare the coercive effectiveness of 323 violent and nonviolent resistance campaigns from 1900 to 2006. Like Gaibulloev and Sandler (2009), the authors find that refraining from bloodshed significantly raises the odds of government compliance even after tactical confounds are held fixed. These statistical findings are reinforced with structured in-case comparisons highlighting that escalating from nonviolent methods of protest such as petitions, sit-ins, and strikes to deadly attacks tends to dissuade government compromise. Chenoweth and Stephan employ an aggregate measure of violence that incorporates both indiscriminate attacks on civilians and discriminate attacks on military personnel or other government officials, which are often differentiated from terrorism as guerrilla attacks (Abrahms 2006; Cronin 2009; and Moghadam 2006). Other statistical research (Abrahms, 2012, Fortna, 2011) demonstrates that when terrorist attacks are combined with such discriminate violence, the bargaining outcome is not additive; on the contrary, the pain to the population significantly decreases the odds of government concessions.