The US is known to have conducted cyber attacks of its own. The programme, code-named "Olympic Games", targeted Iranian nuclear facilities with malicious computer worms. It began under President George W. Bush, but Obama is believed to have ordered an acceleration of the digital attacks when he took office. The details only came to light when the Stuxnet worm, believed to have been developed by the US and Israel, surfaced on the internet. Last month, the Iranian Government denied it had any hand in recent cyber attacks on US financial institutions.
While the American military faces deep budgets cuts, the Pentagon approved a major expansion of its "cyber command" from around 900-strong to some 4900 troops in the next few years, according to the Washington Post.
"There are very, very few instances in cyberoperations in which the decision will be made at a level below the President," an official told the New York Times.
"What concerns us is not the growth of forces but the way it is happening behind the scenes," said a Washington Post editorial.
-Independent