Both political and academic efforts to get to grips with terrorism have repeatedly been hung up on the issue of definition, of distinguishing terrorism from criminal violence or military action. Most writers have no trouble compiling a list of legal or other definitions running into dozens, and then adding their own to it. One well-known survey opens with a whole chapter on the issue; another managed to amass over a hundred definitions before concluding that the search for an 'adequate' definition was still on. Why the difficulty? In a word, it is labelling, because 'terrorist' is a description that has almost never been voluntarily adopted by any individual or group. It is applied to them by others, first and foremost by the governments of the states they attack. States have not been slow to brand violent opponents with this title, with its clear implications of inhumanity, criminality, and - perhaps most crucially - lack of real political support. Equally, states find it quite easy to produce definitions of terrorism. The USA, for instance, defines it as 'the calculated use or threat of violence to inculcate fear, intended to coerce or intimidate governments or societies'; the UK as 'the use or threat, for the purpose of advancing a political, religious, or ideological course of action, of serious violence against any person or property'. Having done this, though, they tend to find it harder to specify the behaviour thus indicted; instead they label certain organizations as 'terrorist' and make membership of them an offence. So terrorism appears to be a state of mind rather than an activity.
The problem here for the detached observer is that state definitions simply assume that the use of violence by 'sub national groups' is automatically illegal. In the state's view, only the state has the right to use force - it has, as academics tend to say, a monopoly on the legitimate use of violence. But outsiders may wonder whether all use of violence by non-state actors is equally unjustifiable, even if it is formally illegal. The very first revolutionary terrorists in the modern age believed themselves justified in opposing with violence a repressive regime in which no freedom of political expression or organization was permitted. And, crucially, many foreign critics of Tsarist Russia - governments included - agreed with them. This has continued to be the case, as when Syria recently, publicly, and embarrassingly refused to endorse the British and American insistence that Arab armed actions against Israel are part of a single global phenomenon of terrorism. Thus arose the notorious adage that 'one person's terrorist is another's freedom fighter'. This relativism is central to the impossibility of finding an uncontentious definition of terrorism. Some writers have suggested that instead of pursuing the will-o'- the-wisp of precise definition (one specialist has recently called terrorism 'a box with a false bottom') it would make more sense to construct a typology of the kinds of actions that are generally seen as 'terrorist'.
It is certainly the case that many kinds of action repeatedly used by terrorist groups - assassination, kidnapping, hijacking - are seldom if ever used in conventional military Conflicts; they do seem to signal a special type of violence. But any such list soon peters out: too many terrorist actions duplicate either military or criminal acts. In any case, it is, in the end, not so much the actions themselves that are characteristic of terrorism, as their intended political function. To get to the real definition of terrorism we need to unpick its political logic. For the core of nearly all definitions of terrorism - the use of violence for political ends - is too similar to the definition of war to be of much use.