Terrorism is considered to be calcultated, and the selection of a target preplanned and rational. The perpetrators know the effect they seek. Terrorist violence is considered to be neither spontaneous nor random.
is this a good definition? Why or why not?
I would disagree especially with the "rational" part of the definition. Terrorism is most often motivated by religious fanaticism and/or political extremism, neither of which are based in rational goals or actions. And as pohnpei argues, there needs to be a clear distinction between terrorism and more conventional methods of warfare.
The most important part of this segment is that nothing is written in stone. The Twin Towers were taken down and so many people were lost because of their planning and an understanding of how those buildings would collapse. However, there have to be situations when terrorists plan to attack and are not successful, even though they have prepared. They may not have prepared enough. There may be a leak of information. Or a group may simply see an opportunity that presents itself in an unlikely and unexpected way, and they may take their shot. There is a certain science to their planning and thinking, but not all of the elements involved answer to science: there is the human element; there is the possibility that things will go wrong. Had any detail of Sept. 11th gone awry, the outcome might still have seen some disaster, but there is no guarantee that an outcome like the plane being forced down in Scranton, PA, might not also have taken place before one of the other two planes in New York hit its intended target.
And in terms of rational? I think the terrorists were crazy: like kamikaze pilots in World War II. They tend to be fanatical, and that does not seem rational as much as overly emotional.
Perhaps a better definition is that terrorism is an act that is planned, but conducted in an surprising way to instill terror. The last part is key. Terrorism is to instill terror. This point must be basic. Also we need to include within this orbit, the idea that terrorism seeks to attack areas that are central to community life and the functioning of society. In this sense, it is to alter our lives.
I don't think that violence in a neighborhood qualifies as terrorism. Basically, the -ism on the end connotes a political aspect to terrorism- i.e people, organizations, or states using violence and terror to some political end.
The concept of terrorism almost seems to imply a kind of military action. Certainly in times past, large scale armies would attempt to instill terror in opposing forces and those that supported them. Perhaps terrorism is simply warfare on a small scale...
Terrorism usually involves the preplanned use of violence against unarmed, unprotected civilians when no formal declaration of war exists. The purpose of terrorism, as the name implies, is to inspire terror in civilian populations so that they will pressure their governments to agree to whatever demands the terrorists happen to be making.
Terrorism certainly doesn't have to cause a loss of life. It can occur through manipulation of the Internet or other electronic devices. It can occur on much smaller scales, such as through criminal acts in neighborhoods which can create fear among residents. I do believe that in most cases, terrorist acts are planned, though randomness can be just as successful as specific targets.
You can't define terrorism in these ways (either Post 1 or 2) because nothing in your definitions would differentiate it from military action which is preplanned and rational and violent and meant to cause large scale loss of life. (BTW, I can't really accept that last aspect of the definition because even killing one or two people, depending on how/where it is done would seem to be terrorism.)
I'd define it as any act of violence meant to instill fear in people for the purpose of advancing some political or social goal that mainstream society disapproves of.
I know it's not a perfect, objective definition, but you can't really define terrorism objectively.
I think terrorism is usually planned in advance, but I would define it as any act of violence intended to cause large-scale loss of life. That usually does involve advanced planning. However, I disagree that terrorist violence cannot be random. Some terrorists just want to cause panic. That after all, is why it's called terror-ism.