nullum crimen sine lege
...you gotta define it before you can prosecute or punish an act (like 'terrorism')
Obstacles to a comprehensive International definition of 'terrorism"
Bassiouni notes: "to define "terrorism" in a way that is both all-inclusive and unambiguous is very difficult, if not impossible. That is why the search for and internationally agreed upon definition may well be a futile and unnecessary effort."
Sami Zeidan, a Lebanese diplomat and scholar, explained the political reasons underlying the current difficulties to define terrorism as follows:
"There is no general consensus on the definition of terrorism. The difficulty of defining terrorism lies in the risk it entails of taking positions. The political value of the term currently prevails over its legal one. Left to its political meaning, terrorism easily falls prey to change that suits the interests of particular states at particular times."
"The Taliban and Osama bin Laden were once called freedom fighters (mujahideen) and backed by the CIA when they were resisting the Soviet occupation of Afghanistan. Now they are on top of the international terrorist lists". "Today, the United Nations views Palestinians as freedom fighters, struggling against the unlawful occupation of their land by Israel, and engaged in a long-established legitimate resistance, yet Israel regards them as terrorists."
Israel also brands the [Hezbollah] of Lebanon as a terrorist group, whereas most of the international community regards it as a legitimate resistance group, fighting Israel's occupation of Southern Lebanon."
"The repercussion of the current preponderance of the political over the legal value of terrorism is costly, leaving the war against terrorism selective, incomplete and ineffective." partially pasted from >> http://en.wikipedia.org/wiki/Definitions_of_terrorism
FBI Definitions of Terrorism in the U.S. Code >> read it here >> http://www.fbi.gov/about-us/investigate/terrorism/terrorism-definition
'just sayin'