Most young people in the US will never have any direct experience of terrorism, but in certain circumstances even heightened awareness and elevated vigilance in society may be enough to do psychological damage.

Writing in Clinical Psychology: Science and Practice Jonathan S. Comer and Philip C. Kendall reason that the goal of terrorism “is to threaten and intimidate a population much larger than that of the immediate victims … terrorism is designed to demoralize its targets by violating the basic assumption that one is safe”.

On that basis they go on to assess how far the attacks of recent years have succeeded in that grim objective by terrorizing children.

Most of the 33 studies they review focus on children who have experienced terrorism at first hand by living in a city that has been attacked and/or losing a loved one as a result. It is no surprise to find that these children are more likely to suffer from a variety of psychological problems – most notably post-traumatic stress disorder (or PTSD) – than others who have not been affected so directly.

However, other studies under their scrutiny examined the effect on children of being exposed to media coverage of terrorist acts. And here the evidence suggests that terrorism tends to succeed in distressing not only direct victims but others as well. Exposure to images of terrorism and information about it are strongly associated with PTSD and with other anxiety symptoms among young people located more than 100 miles from the seat of a disaster.

Writing from Temple University, Philadelphia, Comer* and Kendall stress that better investigation is needed into the impact of terrorism on children directly and indirectly exposed as well as the most vulnerable types of child. They also call for research on what they call “secondhand terrorism.”

Disproportionate media presentations of the possibility rather than the probability of being a direct victim of terrorism contribute to omnipresent threat and insecurity, countless false alarms, and pervasive distressing anxiety, the authors say. Quite how this changed climate is affecting the development and functioning of children, however, is unknown.

Research on the effect of natural disasters on children gives some clues. But unlike hurricanes and earthquakes, terrorist acts are committed by humans, have malicious intent, and are difficult to predict. Such particulars, Comer and Kendall suggest, warrant a great deal more research if we are to help children to cope.

• Summary of “Terrorism: The Psychological Impact on Youth” by Jonathan S. Comer and Philip C. Kendall in Clinical Psychology: Science and Practice, 2007, Volume 14, Issue 3, pp 179–212.

*Jonathan Comer has since moved to Columbia University/New York State Psychiatric Institute