Are our civil liberties fundamentally at odds with national security concerns in the age of nuclear terrorism? Three prominent panelists recently debated the issue, and Hannibal was there to report on their exchange. Hannibal, who covers the technological and social aspects of national security for Ars, also weighs in with his own thoughts, and provides some historical context for the debate.

Posner stated that the criminal justice system relies on deterrence and incapacitation to address crime. The "deterrence" part stems from the potential criminal's presumed desire to avoid incarceration at all costs. Clearly, the deterrence value of the threat of incarceration is exactly zero to a suicide bomber, so in that respect the criminal justice system is quite poorly equipped to prevent terrorism. Furthermore, the criminal justice system presumes a crime rate, and works to keep that rate down to manageable levels. In the age of nuclear and biological terrorism, Posner argued, we can't really afford a "terrorism rate," even if that rate is really low. All it takes is one spectacular attack to do us in, he reminded the audience.

The issues that the three panelists—all important figures in their respective areas of law—addressed are among the weightiest and timeliest problems that we face today. Read on to get a full sense of the contours and direction of the civil liberties vs. national security debate from three of that debate's most knowledgeable voices.