After 9 / 11 : Is It All Different Now ?

Using time-series procedures, we investigate whether transnational terrorism changed following 9/11 and the subsequent US-led " war on terror. " Perhaps surprising, little has changed in the time series of overall incidents and most of its component series. When 9/11 is prejudged as a break date, we find that logistically complex hostage-taking events have fallen as a proportion of all events, while logistically simple, but deadly, bombings have increased as a proportion of deadly incidents. These results hold when we apply the Bai-Perron procedure where structural breaks are data identified. This procedure locates earlier breaks in the mid-1970s and 1990s. Reasonable out-of-sample forecasts are possible if structural breaks are incorporated fairly rapidly into the model. Thousands of dangerous killers, schooled in the methods of murder, often supported by outlaw regimes, are now spread throughout the world like ticking time bombs, set to go off without warning… In a single instant, we realized that this will be a decisive decade…(Bush 2002). President Bush's " State of the Union " remarks strongly suggest that everything changed on 11 September 2001 (henceforth, 9/11) with the world now confronting a far-flung network of terrorists, bent on heinous attacks. While there is no question that perceptions changed and deep-seated fears arose that fateful day, there has been no data-based analysis on how transnational terrorism (i.e., terrorism with international implications or genesis) differs, if at all, since 9/11. The perception on the street and the reporting in the news media is that terrorism is now different. But is transnational terrorism really different after 9/11 and, if so, how is it different? The four simultaneous hijackings on 9/11 represent watershed terrorist events in a number of ways. First, the carnage associated with 9/11 was unprecedented: the number of people killed was as great as all deaths from transnational not require a weapon of mass destruction (WMD) to cause mass casualties and over $90 billion in losses. Third, 9/11 underscored the brutality that some fundamentalist terrorists will undertake. Terrorist experts had warned prior to 9/11 that religious-based terrorists viewed nonbelievers as legitimate targets and sought maximum carnage (Hoffman 1997). Fourth, 9/11 created a greater vigilance on the part of industrial countries that have greatly augmented their expenditure on homeland security. Since 2002, the budget supporting the activities of the US Department of Homeland Security (DHS) grew by over 60% to $36.2 billion for fiscal year 2004 2 (DHS …