From Sputnik to Stuxnet, CSIS cyber expert Denise Zheng explores war in the 21st century by Brian Contreras on July 21, 2017 share Iran, 2012: Hackers overload the websites of several major American banks in a large-scale denial-of-service attack, temporarily shutting down online access to users’ bank accounts. North Korea, 2014: The emails of top Sony executives are