It is insufficient to protect ourselves with laws; we need to protect ourselves with mathematics.

It's frustrating; terrorism is rare and largely ineffectual, yet we regularly magnify the effects of both their successes and failures by terrorizing ourselves.

Hardware is easy to protect: lock it in a room, chain it to a desk, or buy a spare. Information poses more of a problem. It can exist in more than one place; be transported halfway across the planet in seconds; and be stolen without your knowledge.

We no longer know whom to trust. This is the greatest damage the NSA has done to the Internet, and will be the hardest to fix.

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.

People often represent the weakest link in the security chain and are chronically responsible for the failure of security systems.

It is poor civic hygiene to install technologies that could someday facilitate a police state.