In an interview with FRANCE 24 in New York, former US counterterrorism czar Richard Alan Clarke described the main threats facing the United States' cyberspace and warned that Russia's cyber weapons could potentially "do a lot of damage" in the US. To explain why this hasn't happened so far, he cited an "unwritten rule" he believes the US and Russia are both following: "[if] you don't attack me, I won't attack you".
Clarke, who served as US counterterrorism czar between 1998 and 2003, also explained why China has never done significant damage to American cyberspace: Chinese authorities know that a major cyber attack against the US would trigger a "traditional" retaliation from the US: "bombs, missiles, ships and airplanes".