"It is likely that in the aftermath of the attack on the United States that we will see an upsurge of separation anxiety behaviour in children," says counselling psychologist Marie Murray.
These are strangely reassuring words, considering that many parents will already have experienced their children's distress in reaction to the events they have witnessed on television. As parents, many of us are ourselves feeling anxious, though we try not to show it.
"When all that was safe, secure and inviolate has been violated, we respond in very specific ways. Predominately these responses are primitive and designed to keep our children and ourselves safe from harm by keeping physically close to each other," says Murray.
Wanting to be close is an instinctive response to attack. So we may understandably feel as anxious about leaving our children - especially if we have to travel abroad without them - as they feel about being "left" by us.
The attack on the United States punched a hole at the very core of our security. People in Enniskillen, Omagh and Canary Wharf experienced this same sense of having the ground pulled out from under them. When our security is attacked, then in our imaginations anything can happen.
"What people usually think of first is their own particular family," says Murray. "Global fear becomes personal fear; the emotional consequences of international events are often exhibited in local and family reactions. We think: 'If the world can be attacked then how safe is my family?' Once the core of inner security is invaded then fear generalises into many other areas of our lives." If life is fragile, if a secure world can be transformed into an insecure place overnight, then people become very conscious of the importance of family and become determined to keep family safe by keeping them close.
Some children will be affected more than others. Says Murray: "The sudden, unexpected, personal invasion of what was previously a secure and predictable world is likely to cause regression in children who have incorporated the emotional fear and distress of adults at the events. Many children will have seen images lifted out of apocalyptic movies come into their homes as reality. They will have witnessed the shock of their parents. They will have become aware of a day free from school to mourn what has been described as the end of civilisation. Whatever their understanding of events they will not have failed to perceive, to hear and feel that something catastrophic and unprecedented has happened." For the first time in their lives, our children are not hearing us laughingly reassuring them that "it's not real, it's just a movie". Having to tell them that it's real is very painful, when all our lives as parents we have been protecting them.