Sony hack fallout: What can the U.S. do against North Korea?

And it's not just about cybersecurity. It's about how to punish and deter what's pretty much a pariah state whom the U.S. has struggled to punish and deter for decades, "long before James Franco and Seth Rogen were in Freaks and Geeks," said Peter W. Singer, the author of ​Cybersecurity and Cyberwar: What Everyone Needs to Know, and the strategist and senior fellow at New America foundation.