"In his first 18 months in office, General
Nakasone has raced to bolster Cyber Command’s
authority to act preemptively — and its
preparations to respond to attacks. New,
classified directives given to him by Mr. Trump,
and built upon by Congress, allow Cyber Command
to place 'implants' of malicious software inside
foreign networks without lengthy approval
processes that run up to the president. Congress
has called such efforts part of 'traditional military authority.'

Iran has reportedly been a major target ­ no
surprise, since General Nakasone was a key player
in designing a plan called “Nitro Zeus” to shut
down Tehran and other Iranian cities in the event
of a war. The idea was to put together an attack
so devastating that Iran might surrender without a shot being fired.”

https://www.nytimes.com/2019/09/23/world/middleeast/iran-cyberattack-us.html