From the introduction: "In late November 2014, Sony Pictures Entertainment confirmed it was the victim of a cyber attack that crippled its networks and stole large quantities of personal and commercial data. On December 19, the U.S. Federal Bureau of Investigation (FBI) publicly identified North Korea as responsible for these crimes, describing the attack as 'destructive' and 'coercive' in nature. President Obama pledged the United States would respond 'proportionately' and 'in a place and time and manner that we choose.' On January 2, 2015, the United States imposed financial sanctions on North Korea's arms industry as a 'first step in retaliation.', Analysts and news media have suggested further steps could include listing North Korea as a state sponsor of terrorism, bringing down its propaganda websites, and targeting its computer hardware, with a kinetic response termed 'the remotest of possibilities.' U.S. officials reached out to China's government following this attribution in an effort to 'share information,' 'express our concerns,' and 'ask for their cooperation,' as stated by one representative. The United States reportedly asked specifically for assistance in a 'blocking action' to eliminate North Korea's ability to carry out future attacks, as Chinese state-owned enterprise China Unicom is a crucial conduit for nearly all of the regime's telecommunications. Beijing has yet to publicly respond to the U.S. overture or officially acknowledge North Korean involvement, stating only that China 'is against all forms of cyber attacks,' including those launched by a state 'using facilities beyond its own national borders against a third country.' As China has received attention as a potential factor in this attack, is in a unique position to influence North Korea, and is a key player in the development of international norms in cyberspace, its reactions to U.S. decisions on these matters are of particular interest."
U.S.-China Economic and Security Review Commission: http://www.uscc.gov/