Terrorism Before and After 9/11

Was 9/11 the opening salvo in a new age of terrorism? Some argue that this act ushered in a more chaotic world. Others contend an increased focus on terrorism in the past 15 years is the result of conflating terrorist activity with insurgency. We shed light on these claims by analyzing data on domestic and transnational terrorist incidence from 1989 to 2014. The evidence suggests that the years since 9/11 have been different from those preceding them. Once the prevalence of conflicts is accounted for, the post-9/11 era is a significantly less terror prone period than the years before it. A country not suffering civil conflict was upwards of 60 percent more likely to experience terrorism prior to or during the year 2001 than since. However, the opposite trend holds for those countries with a higher proportion of Muslims. Prior to 2001, countries with higher Muslim populations experienced less domestic terrorism. Since 9/11, these countries have experienced significantly more terrorism — both domestic and international — than they had previously.