History has taught us: never underestimate the amount of money, time, and effort someone will expend to thwart a security system. It's always better to assume the worst. Assume your adversaries are better than they are. Assume science and technology will soon be able to do things they cannot yet. Give yourself a margin for error. Give yourself more security than you need today. When the unexpected happens, you'll be glad you did.

If you think technology can solve your security problems, then you don't understand the problems and you don't understand the technology.

Societies without a reservoir of people who don't follow the rules lack an important mechanism for societal evolution. Vibrant societies need a dishonest minority; if society makes its dishonest minority too small, it stifles dissent as well as common crime.

It's certainly easier to implement bad security and make it illegal for anyone to notice than it is to implement good security.

But in this country, while you have to be competent to pull off a terrorist attack, you don't have to be competent to cause terror. All you need to do is start plotting an attack and - regardless of whether or not you have a viable plan, weapons or even the faintest clue - the media will aid you in terrorizing the entire population.

I tell people: if it's in the news, don't worry about it, because by definition, news is something that almost never happens.

Computer security can simply be protecting your equipment and files from disgruntled employees, spies, and anything that goes bump in the night, but there is much more. Computer security helps ensure that your computers, networks, and peripherals work as expected all the time, and that your data is safe in the event of hard disk crash or a power failure resulting from an electrical storm. Computer security also makes sure no damage is done to your data and that no one is able to read it unless you want them to.