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Ten years after the attacks of September 11, 2001, it almost goes without saying that the acts of grotesque violence committed on that day have had enormous effects on national security law and policy worldwide. To be labeled a terrorist, or to be accused of involvement in an act of terrorism, carries far more severe repercussions now than it did ten years ago. This is true under international law and under domestic law in nations that have dealt with serious national security concerns for many years.

Given the U.N.’s global mandate to combat terrorism and that being defined as a terrorist can have widespread legal implications, this Article seeks to address how legal definitions are shaped and analyzes the lack of a globally accepted definition of terrorism in the context of domestic counterterrorism obligations. This Article addresses a significant historical gap in examining the interplay between international obligations and domestic definitions, the previously overlooked history and evolution of those definitions, and the potential rule of law issues arising from the definitions in their current form.

In examining counterterrorism law in the United States, the United Kingdom, and India, it is clear that definitions of terrorism under various domestic laws have been repurposed from one legislative context to another and broadened in application, particularly since September 11. This has led to the arguably unintended consequences of disparate impact on outsider groups and the unmooring from rule of law principles. Since neither international norms nor domestic courts provide a significant check against creeping definitions, legislatures must take proactive steps to combat potential overreaching in applying the label of terrorism.

Recommended Citation

33 U. PA. J. Int'l L. 1 (2011)