Back when I was designing computer systems, there were many things to take into consideration. The more obvious ones were the various functions and data, where they were located, how things were connected, processes, interfaces, and the usual gory details of systems design.

But my design documents would also have a section labeled "Pathology." This would be a study of the abnormal functioning of the system -- what would happen when different things went wrong, how they would be detected and reported, and how the normal order of things would be restored.

Other system designers that I worked with thought that this was wasted time, and designed their systems as if nothing would ever go wrong.

So I would ask them, "Who is more dangerous, the terrorist or the fool?" Without exception, they answered that outsiders, trying to damage the system were the biggest threat, and that they had put in all sorts of safeguards such as firewalls, passwords, and complex safety measures.

I always thought that the reverse was true. The fools were far more of a threat. Look at it this way: The fools outnumber the terrorists, they're already inside your organization and on your payroll, they strike without warning or pattern, and they are only trying to help. The biggest danger to a system is "friendly fire."

Think of all of the times that you were unable to access a computer system and ask yourself how many were due to malicious acts and how many were due to someone pressing the wrong button somewhere deep within the system.

What brought on these thoughts is that today is the 20th anniversary of the largest atomic disaster in history, the explosion at Chernobyl which caused more damage than all of the terrorist acts of the last 100 years. The explosion occurred during a test of the reactor's cooling system, during which the engineers overrode safety procedures and equipment and ignored all the warnings from the system. Certainly a victory for the fools.

And I look at our administration's efforts in the "War on Terror." In trying to control terrorism, they have caused many times the death and destruction that any terrorist organization could dream of.

Another great victory for the fools.