It could be the greatest strategic irony of the last twenty years: the American lead in digital technologies ' upon which our financial, communications and defense systems are built, and on which they depend ' may also represent a serious American Achilles heel. The sophistication of our mobile phone networks, of the GPS system that guides air traffic, even of the networked command-and-control that drives our power grids, may be without rival. But it also provides one great big and sprawling target to enemies determined to discover the choke points that can cripple us in a time of war. At least that's the scenario as described in various, and increasingly alarmed media accounts, especially in the wake of incidents like the hacking of Google last year, by digital assailants often described (without clear confirmation) as being based in China. It's indeed alarming, to contemplate fighting the next war with both hands tied behind our backs because a canny enemy figured out how to shut us down electronically. Alarming ' but possibly, also, alarmist? Can we really be that vulnerable? Is our digital undergirding really that exposed, especially given that the Internet itself ' the foundation of all this critical connectedness ' was itself initially developed as a military undertaking? Even if our enemies ' state enemies or terrorists ' manage to cause damage in one corner of American cyberspace, don't we have enough redundancy built in to protect us? As one technology writer has put it, this is one of those topics where the internet press likes to get worked up into a lot of 'heavy breathing.' So which is it? Are we at existential risk in the event of a well coordinated cyber attack, and if so, are we taking measures to protect ourselves? Or will the first cyber war be a war we are already positioned not only to survive, but to win?