The recent shooting of Army personnel in Arkansas by a Muslim apparently motivated by Islamic militancy, which followed a shooting days before of a notorious abortionist, raises the question of the definition of terrorism, in order to answer the question about whether such domestic political acts of violence constitute terrorism. These attacks were examples of militancy, not terrorism.
The word terrorism has been used so broadly that it has become diluted. Thus, its degree of evil has been minimized. When one labels all forms of violence as terrorism, one minimizes the particular evil of terrorism. Indeed, terrorism has been confused with all acts of political violence -- and even some that are not political. On the other hand, terrorism has been confused with other great evils such as mass-murder motivated by revenge or genocide. In short, terrorism has become so broadly used a word that it has lost its meaning.
Terrorism is the deliberate targeting of innocent civilians with violence or the threat of violence in order to intimidate a certain populace into demanding that its government change its policies according to the wishes of the terrorists. Although I could write an essay explaining each point in great detail, I shall let the above definition suffice for now.
Indeed, not all forms of political violence are acts of terrorism. Terrorism is a strategy defined by its target, not its cause. Whether a certain cause is just or not is irrelevant to the definition of terrorism. Therefore, it is not true that one man’s terrorist is another man’s freedom fighter. The particular evil of terrorism is that it targets innocent civilians instead of political or military leaders.
Terrorism is not defined by its methods, either. A bombing, for example, even if motivated by political purposes, is not necessarily a terrorist attack. A bombing may be motivated by political opposition or revenge, or be intended to target only a few individuals, neither of which would be intended to intimidate the populace.
Those who target political leaders or military forces are "militants" and could be called "insurgents" or "guerrillas," while those who militants who target property are "saboteurs" specifically. Attacks that are targeted on specific individuals with whom the attacker has a grievance are not terrorists because the target is not innocent civilians with the intent to intimidate them. In contrast, although some people might be frightened by attacks that target others, such attacks are not terrorism because the intent of a terrorist is to intimidate all innocent civilians within a certain populace, not to harm just certain individuals.
Most political acts of violence that have occurred within the United States have been called "terrorism" by the media, politicians and other commentators. These acts are not terrorism, but are militancy of some kind or another, in contrast to the September 11 Attacks. All such militancy is unacceptable and must be prevented or punished, but it is not the same thing as terrorism. Even the legitimate exercise of self-defense by the United States or others is called "terrorism" by its foreign and domestic opponents, but the charge is baseless because legitimate self-defense targets enemy military forces in order to prevent more attacks, not innocent civilians.
The purpose of the War on Terrorism is to eliminate the threat of terrorist attacks against Americans or their interests, but although one of its aspects is to eliminate terrorism against the United States in particular, its broader aspect is to eliminate all militancy that is hostile to the U.S. Islamic militancy, both abroad and domestically, especially continues to pose a threat to Americans. It must be resisted in all its strategies and tactics.