Terrorism is a crime against the mind. We win by refusing fear.

People don't understand computers. Computers are magical boxes that do things. People believe what computers tell them.

The mantra of any good security engineer is: "Security is a not a product, but a process." It's more than designing strong cryptography into a system; it's designing the entire system such that all security measures, including cryptography, work together.

If someone steals your password, you can change it. But if someone steals your thumbprint, you can't get a new thumb. The failure modes are very different.

Air travel survived decades of terrorism, including attacks which resulted in the deaths of everyone on the plane. It survived 9/11. It'll survive the next successful attack. The only real worry is that we'll scare ourselves into making air travel so onerous that we won't fly anymore.

The whole notion of passwords is based on an oxymoron. The idea is to have a random string that is easy to remember. Unfortunately, if it's easy to remember, it's something nonrandom like 'Susan.' And if it's random, like 'r7U2*Qnp,' then it's not easy to remember.

Trying to make bits uncopyable is like trying to make water not wet. The sooner people accept this, and build business models that take this into account, the sooner people will start making money again.