u.s. infrastructure? >> absolutely. >> a cyberattack? >> yes. special power, natural gas distribution, transportation networks, air traffic control system, financial sector, all of those things. >> you've just shut down the u.s. >> yeah. basically, yeah. >> every day he's fighting a war that is constantly shifting against increasingly familiar adversaries. >> we are in a battle, if not an actual war, in cyberspace and i want folks to understand and appreciate that. >> with multiple actors? >> yes. >> china, russia, iran? >> north korea, eastern europe. >> countless enemies launching a staggering number of attacks, tracked here in the nsa's cybercommand center. >> how many cyberattacks do you