A generation ago, "cyberspace" was just a term from science fiction, used to describe the nascent network of computers linking a few university labs. Today, our entire modern way of life, from communication to commerce to conflict, fundamentally depends on the Internet. And the cybersecurity issues that result challenge literally everyone: politicians wrestling with everything from cybercrime to online freedom; generals protecting the nation from new forms of attack, while planning new cyberwars; business executives defending firms from once unimaginable threats, and looking to make money off of them; lawyers and ethicists building new frameworks for right and wrong. Most of all, cybersecurity issues affect us as individuals. We face new qu...