Al Quaida tried at some time to attack only American military targets (thus delimiting itself from terrorism), but the attack on WTC in New York is clearly a terror act. The people killed were not representatives of the state, the planes used were not military, and the buildings did not belong to the state). However the attack on the Pentagon was not a terror act, but a war act.
A practical aspect should be noted connected to the tendencies of terrorism: who has vocation to build, has no 'vocation' for terrorism. To build planes, buildings and so many other material goods supposes an immense effort on scientific and technological levels, in labour organisation, on the social and cultural level. Those who know how difficult these things are done, and how many causes can block easily this process, will not have the tendency to destroy material goods.
We change now the discussion and will refer to the individual terrorists existing in any society. Serial killers exist, and others, who kill randomly innocent people. By definition, they are also terrorists, even if they act alone, without any connection to a group.
It is clear that a society can't protect itself against terrorism through stricter laws. The tougher laws will determine the disappearance of exactly those facilities, which permitted the progress of the society. Multiple levels of security will produce the fragmentation of the society. Thus, due to the reduction of the capability to communicate, the level of generalised schizophrenia increases. This could lead to a disaster on long-term.
Not any person who refuses symbolic models will have terrorist tendencies. There are adaptation forms to a world that evolves in another direction than the one desired by some. In the attempt to find the individuals with tendencies towards terrorism, one can consider a few aspects:
1. Children who have been normal at birth, but have been abused during childhood, are on the highest level of risk. Individuals aggressed explicitly or implicitly by the environment, can build illegal models, which enter their PSM; the ones with difficulties of communication have the tendency to build too short-range models for understanding the world they live in (schizophrenia XS 1 and 2). 2. The stresses generating shielding models and illegal models can affect any person, as society is very complex. For persons from 'imagistic' countries, an important source of stress is the assimilation and operation of advanced symbolic models. Forcing them to evolve from an image platform to high level symbolic models can destabilize the structure of models. For the 'symbolic' countries, the same can happen on a more reduced scale. 3. The isolation or elimination from society of the individuals with clear tendencies towards the destruction of the democratic system. 4. Relaxation in the protection of privacy. The so-called right to privacy hides important sources of stress both for the people protected by this right, and the ones around him/her. If everybody would accept the opening of their privacy, the society as a whole would have less real problems.
The working principle of democracy should be somewhat modified, i.e. a democratic system protects only those who respect democracy. Thus, the individuals who fight against democracy should not be protected by the democratic system.
Conclusion: The evolution of society is based on symbolic models. Those who have not the capacity to follow this trend will 'run for shelter' into image models. Slowly a break will occur between 'symbolic' and 'image' people. The 'image' people, who are not those who push the society forward, will see that, from their point of view, society goes into a wrong direction. One of the extreme answers to this situation is terrorism.
Warning: The individuals based on image models do not accept logical argumentation, because logic is an exclusive characteristic of symbolic models.
ETA 11: Problems of human brain evolution