This study empirically tests what has become a central component of US anti-terrorism policy under the Bush administration: that terrorism is a byproduct of illiberal political and economic systems. Employing a series of statistical analyses on incidents of terrorism in 153 countries from 1986 to 2003, the author finds that variables measuring democracy and degree of economic openness are not significant predictors of terrorism. However, the study does find that experience of state failures is significant, thus providing empirical backing for a small, descriptive body of scholarship linking failed states to terrorism.
Piazza, James A. 2008. "Do Democracy and Free Markets Protect Us from Terrorism?" International Politics 45 (January): 72-91. https://link.springer.com/article/10.1057/palgrave.ip.8800220