Katie, at Elocutio, posed this question What's your verbal score? . MacZed at the thecrisesblog gave the heritage dictionary definition. What follows is my response to the dictionary definition and something you probably don't want to read all the way through (my answer is way at the end; second paragraph prior to the footnotes).

The problem with a definition as broad as the dictionary definition, is that it is so broad as to be meaningless: in terms of criminal definitions; and defining who is a terrorist. Violence, and intimidation are used by Law Enforcement daily, but Law Enforcement violence is authorized and discriminatory and therefore, is force, rather than mere violence.
The dictionary definition fails to distinguish between legitimate violence and illegitimate violence. It also fails to distinguish between criminal and political terrorism. Without such a distinction, one is unable to properly confront political terrorism (mere criminal terrorism is best confronted through the criminal justice system.)

What is Terrorism?

Terrorism is a tactic. It is a tactic used by those in a position of weakness. Groups, individuals, and states that are sufficiently strong enough to confront their opponent choose legitimate tactics and legitimate targets[1].

Any definition of terrorism is bound to have its detractors because it is either too broad or too narrow. The best definition of terrorism that I have seen is a negative argument: Martha Crenshaw defines terrorism by what it is not, namely guerilla warfare. Crenshaw states that guerilla warfare is characterized by its use of legitimate military tactics, its targeting of legitimate military targets, and that it has a chance of success. These are the dominant features. Civilians may occasionally be targeted by guerilla groups but they are not the primary target as they are with terrorist groups, such as Islamic Jihad or HAMAS.

This is a useful start. It tells what not to look for when considering what is and what is not terrorism. This definition, however, suffers from the defect of not being specific enough. It cannot really be said to be too broad because it is more of a, “I’ll know it when I see it,” approach.

From this starting point we may add some elements to build a definition of terrorism. It quite obviously involves the inflicting of fear or terror through the use of violence or threat of violence. Where definitions begin to differ at this point are two things: the motive and the identity of the person or group inflicting the terror and who the terror is directed at[2].

Motive

Motives can be divided into religious, political, or any of countless other categories. Other than criminal terror (which will not be addressed here), all motives may be boiled down to a political core. This is because the motive is, essentially, about control—control of economic tools, control of land, the ability to define a religion, or any other means of control.

We now have terrorism defined as, “Political violence, or the threat of violence…” We now need to consider identities. Who commits the act or instills the fear, and who is the violence directed at, or who is the violence intended to influence[3]?

Identity

Now that we have the act and the motivation behind the act defined, we can determine the identities by determining who commits the acts (and later who they are directed at) that meet the definition to this point. These may be individuals, sub-national groups, or states[4]. Theodore Kaczynski (the Unabomber) is an example of an individual terrorist. McVeigh is best understood as a member of an amorphous, undefined group. Other groups are the usual suspects: Israel’s myriad terrorist opponents; India’s foes in Kashmir; the Moro Liberation Front in the Philippines; the Armed Islamic Group in Algeria; and on and on. Examples of modern terrorist states are the Sudan (internal targets) and Iran (external targets)[5].

Individuals tend to have idiosyncratic goals[6] and resist anything other than a broad classification. Such an individual may wish to bring attention to a perceived grievance through a spectacular event, or this individual may with to launch a campaign, as did the Unabomber.

Sub-national groups may be seeking independence, such as elements of the Provisional Irish Republican Army, or the original Irish Republican Army under Collins and De Valera. Sub-national groups may also be seeking a more abstract goal, such as the re-establishment of the caliphate over the Umma.

States typically are trying to control minority[7] populations, such as the mass deportations of the Soviet Union, under Stalin. States may also be engaging in an attempt to ethnically ‘cleanse’ their territory, such as Serbia or the Sudan. These states may also be suppressing dissent, as was found in military juntas in Latin America in the 1970’s. States may also engage in terrorism against outside enemies, as North Korea does when it kidnaps Japanese citizens, or attempts to infiltrate and sabotage the vastly more successful South Korea. The common goal in all of these is the attempt to direct the citizenry’s attention on something other than on the failures of the terrorist state.

At this point is when Crenshaw’s discussion is the greatest use when defining terrorism. When individuals, sub-national groups, or states consistently use illegitimate tactics against illegitimate targets is when they may be described as terrorists.

The definition of terrorism that we now have is:

Terrorism is the consistent use of non-military tactics, by individuals, sub-national groups, or nations, against non-military targets in an attempt to gain, or exert, control over an identified ‘other.’[8]

Guerrilla warfare may transgress legitimacy, with respect to targets and tactics, occasionally, but the difference is that such transgressions are part and parcel of terrorism. Guerrilla status as guerrillas does not justify any terrorist acts committed by guerrillas in the course of their guerrilla warfare. Terrorists may use legitimate tactics, such as ambushes, but this does not justify their terrorist acts.

[1] I begin my definition of terrorism at this point.

[2] It may be argued that these are three but I will treat the inflicting entity and the terrorized as two sides of the same coin.

[3] These are not always the same people. For example, an Islamic Jihad suicide bomber who detonates his belt bomb in a crowded restaurant is not intending to influence the owners’ of the restaurant, or the typical patrons of the restaurant, rather, the intended targets are the politicians who can make the decisions desired by the leadership of Islamic Jihad. Granted, considering the relevant terrorist organizations in the “occupied” territories reject Israel’s right to exist, I do not believe that Israel’s government will volunteer to have their citizens exiled, enslaved, or murdered.

[4] Frantz Fanon believed that only states were capable of terrorism. He described terrorism as hindering the people’s revolution, or in some other way interfering in the eventual establishment of a Soviet-style worker’s paradise.

[5] The difference between these—internal versus external—may be briefly described by noting the Sudan’s campaign of ethnic cleansing directed at the Christian and animist south-Sudan, or the Sudan’s campaign against African Muslims in the west-Sudan. Their targets are predominantly within the country. Iran’s use of its intelligence agency to assassinate those who criticize Iran or Islam is an example of external state terrorism. Iran’s use of surrogates, such as Hezb’allah, is another example. This distinction is of no practical significance, for the purposes of this discussion.

[6] Goals are distinct from motives—one may be motivated by ideological Puritanism to create a theocracy, for example. In the preceding, the motive is ideological Puritanism, and the goal is to create a theocracy. Also, one may be motivated by the belief that the human race is fallen, with the goal of hastening an apocalypse—see Aum Shrinkyo. These examples demonstrate that goals and motives must be considered as separate entities. Both goals and motives may affect constructed reality, the closed system, or the Doctrine of Necessity in different and distinct ways.

[7] By minority, minority of power is intended. A group may be a majority of the population and, in terms of power, a minority. Iraq under Sadaam Hussein is a good example of this.

[8] This control may be psychological, physical, political, or moral.