On May 21 U.S. Secretary of Defense Robert Gates announced the activation of the Pentagon’s first computer command. And the world’s first comprehensive, multi-service military cyber operation.
U.S. Cyber Command (CYBERCOM), initially approved on June 23, 2009, attained the status of what the Pentagon calls initial operations capability eleven months afterward. It is to be fully operational later this year.
CYBERCOM is based at Fort Meade, Maryland, which also is home to the National Security Agency (NSA). The head of the NSA and the related Central Security Service is Keith Alexander, U.S. Army lieutenant general on the morning of May 21 but promoted to four-star general before the formal launching of Cyber Command later in the day so as to become its commander.
The U.S. Senate confirmed Alexander for his new position on May 7. In written testimony presented to Congress earlier, he stated that in addition to the defense of computer systems and networks, “the cyber command would be prepared to wage offensive operations as well...”  Two days before his confirmation the Associated Press reported that Alexander “said the U.S. is determined to lead the global effort to use computer technology to deter or defeat enemies.”  The conjunction “and” would serve the purpose better than “or.”
The day Alexander assumed his new command Deputy Defense Secretary William Lynn “called the establishment of U.S. Cyber Command at Fort Meade, Md., today a milestone in the United States being able to conduct full-spectrum operations in a new domain,” adding that the “cyber domain... is as important as the land, sea, air and space domains to the U.S. military, and protecting military networks is crucial to the Defense Department’s success on the battlefield.” 
The Pentagon’s second-in-charge is not the only person to refer to cyber warfare as the world’s fifth battleground after those of land, sea, air and space, nor to link the first with the other four.
Indeed, the Defense Department’s Quadrennial Defense Review released earlier this year focuses on “a broader range of military responsibilities, including defending space and cyberspace,”  and the Pentagon’s space operations are now grouped with cyber warfare as the new Cyber Command is subsumed under U.S. Strategic Command (USSTRATCOM), which is in charge of the militarization of space as well as the global interceptor missile project, information warfare and related missions.
In its own words, “USSTRATCOM combines the synergy of the U.S. legacy nuclear command and control mission with responsibility for space operations; global strike; Defense Department information operations; global missile defense; and global command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR), and combating weapons of mass destruction.” 
“U.S. CYBERCOM is a sub-unified command under U.S. Strategic Command, of Offutt Air Force Base in Nebraska. But it will be run out of the super-secretive communications-gathering National Security Agency in Fort Meade, Md.” ...