National-security debates used to be a lot easier when it took a nation-state to raise an army and build an arsenal. To hear some cyber-defense experts tell it, today a cyberwar can be launched by a couple of bored teen-age hackers in one of their basements. While that's a stretch, what about criminal cybergangs? Or nation-states? Or, most insidiously, nation-states that hire such underlings to carry out cyber attacks? John Nagl of the Center for a New American Security and I chat about the vexatious challenge with James Lewis, a cyber-warfare expert at the Center for Strategic and International Studies, and Kristin Lord, who recently oversaw a CNAS examination into the issue.