Cyberattackers pose many threats to a wide range of targets.
Russia, for example, was accused of hacking Democratic Party computers throughout the year, interfering with the U.S. presidential election.
Then there was the unknown attacker who, on a single October day, used thousands of internet-connected devices, such as digital video recorders and cameras compromised by Mirai malware, to take down several high-profile websites, including Twitter.
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Deterrence focuses on making potential adversaries think twice about attacking, forcing them to consider the costs of doing so, as well as the consequences that might come from a counterattack