Iran's willful exclusion of its citizens from the Internet much of the rest of the world knows -- its attempt to take the "worldwide" aspect out of the World Wide Web -- may well indicate weakness in the regime itself. ("If this is what passes for leadership," Schmidt put it, "these guys have a problem.") If so, though, it's a weakness belied by technological capabilities: the Iranian regime, at this point, does have the infrastructural power to filter the Internet. It can censor its citizens with increasingly surgical precision. It can create its own version of YouTube. It can bypass Google and Facebook and other American companies, shaping the experience of the Internet for all but the most technologically savvy of its citizens. "Islamic Google Earth" may be a joke; it may also be, however, a harbinger of what's to come.

There's another concern, too, Cohen pointed out. Internet balkanization could enable autocratic states to "band together" to create cyber-alliances that can collaboratively edit the web in order to enforce shared norms. The collectives might edit comments made about their regimes. They might cooperate to monitor user behavior. They might attempt to enforce their notion of "moral behavior" through censorship and other means.

And they might ultimately engage, Cohen continued, in a kind of "digital ethnic cleansing." Traditional legal and political checks on mass criminality have been developed within and for the physical world, he noted; in the digital, however, those checks are less developed. The web is simply too new. And you could imagine autocratic regimes or other communities taking advantage of that, creating a scenario in which one group finds a way to, for example, filter another group's content from the web. Or to shut down -- or severely slow down -- their Internet access. Or to infiltrate them with malware and/or orchestrate elaborate denial-of-service (DDoS) attacks. One group, in other words, could essentially annihilate the digital existence of another.

And then the perpetrator could simply, Cohen said, "make the whole thing look like technical difficulties." Making punishment or retribution, per physical-world systems, extremely difficult.

What all this comes down to, Clemons suggested, is something that Schmidt and Cohen emphasize in their book: the new need for a "virtual foreign policy." While the physical world and the digital obviously coexist, Schmidt pointed out, we have much more finely established ways to regulate behavior in the physical world. When people in the virtual community begin to misbehave, committing crimes that wouldn't be legal in the physical space, we currently have very few mechanisms for correction. As that reality plays out on the geopolitical stage, he said, you could have "this bizarre situation" in which, say, the U.S. and China have a generally good relationship in the physical world: cash flow, open communications, travel between the two countries, etc. And yet behind the scenes -- in the digital world -- those countries could be, effectively, waging war on each other through their digital infrastructure.

Without a more strategic merging between the physical world and the digital, Schmidt suggested, that scenario could well become reality. For now, Cohen said, the big question looming before us is this: "At what point is a cyber attack so big that its effects spill over into the physical world?" We don't yet know. But there's a good chance we'll soon find out.

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