Systems are complex, so controlling an attack and achieving a desired level of damage may be harder than using physical weapons.

However, leaving everything to the market is not necessarily good for society.

Although cyber attacks have caused billions of dollars in damage and affected the lives of millions, few if any can be characterised as acts of terrorism.

If we take as given that critical infrastructures are vulnerable to a cyber terrorist attack, then the question becomes whether there are actors with the capability and motivation to carry out such an operation.

While the vast majority of hackers may be disinclined towards violence, it would only take a few to turn cyber terrorism into reality.

I favor strategies that encourage industry to include some sort of key recovery capability in their systems which would also address user requirements for access.

We have never really had absolute privacy with our records or our electronic communications - government agencies have always been able to gain access with appropriate court orders.