“…Further, most Western countries changed their counterterrorism laws and increased their spending on counterterrorism measures after the 9/11 attacks, which, ceteris paribus, should make the number of terrorist attacks drop. 3 Instead of looking at the actual attacks, one might, counterfactually, analyze how many terrorist attacks would have happened had it not been for the increased (Bakker, 2006;Nesser, 2008;Taillander, 2001), government reports (US State Department, 1996), Web searches, and searches of newspaper archives (LexisNexis, 2008). The cases have been through a conservative vetting process, excluding those without adequate documentation of events, plots, and perpetrators.…”