NATO leaders agreed on Friday that a large-scale cyberattack on a member country could be considered an attack on the entire U.S.-led alliance, potentially triggering a military response.
The decision marks an expansion of the organization's remit, reflecting new threats that can disable critical infrastructure, financial systems, and government without firing a shot.
"Today we declare that cyber defense is part of NATO's core task of collective defense," NATO Secretary-General Anders Fogh Rasmussen told a news conference.
In 2007, a series of crippling cyberattacks paralyzed much of NATO member Estonia in an apparent response to a dispute over the movement of a Soviet-era war memorial. Most Western experts suspected the Kremlin was responsible, but Russia denied it.
(Reporting by Adrian Croft; editing by Paul Taylor)