SEPTEMBER 11 changed our fear threshold. The audacity of the attacks and the scale of the suffering has left the world in a waking nightmare. What happened was beyond the darkest imaginings of Hollywood or horror fiction and has made any outrage seem possible. If one of our bad dreams has come true, why not others?

Fears rooted deep in our sub-conscious were brought to the surface by the assault on America. Germ and biological warfare has long been technically possible, but it seemed a distant threat until now.

Suddenly, there is a huge demand for gas masks. People have read reports about terrorists supposedly plotting to rain death from the skies using hijacked crop-spraying planes. They have heard warnings about the dangers of germ warfare from a body as respected as the World Health Organisation. Naturally, they want to do anything they can to protect their families.

Unlike the Gulf War, our fighting forces are not the only ones in the front line. The people who died in America were civilians going about their normal daily business. We all feel like targets now.

But it is crucial we keep our fear under control. The main aim of terrorists is to spread terror; if we allow ourselves to be ruled by dread then they have won.

Even in these tense times, the risk of anyone close to us being harmed by terrorism remains tiny.

Nerves will be frayed by news of local authorities upgrading their civil defence plans, hospitals revising their major incident plans and the Hawkhills centre at Easingwold hosting seminars on the terrorist threat.

Yet we should take reassurance from these activities. Experts in every field, civil and military, are striving tirelessly to minimise the threat.

Meanwhile, we can all play our part by remaining vigilant and reporting suspicious behaviour. In that way we wrest control of our lives back from the terrorists. By defeating our fears, we defeat their aims.

Updated: 10:16 Tuesday, September 25, 2001