A former general counsel for the NSA has warned that there is "no taboo" around the use of cyber weapons.

Stewart Baker, now a partner at Steptoe & Johnson, outlined his views on cyber warfare at the Cyber Security Summit in Minneapolis, which he believes tally with the opinions of US Congress, the country’s legislative body.

"Cyber weapons are not like nuclear weapons and the thought that they’re better if you’re fighting a war is disconcerting because there’s no taboo in using them," he said.

"The idea that you can’t use cyber weapons in a civilian context has already been undermined by states that actually use them. The likelihood that we can establish a norm against using them in order to protect civilian populations is limited."

Raising the Stuxnet virus which targeted Iranian nuclear power , Baker noted that similar attacks could be brought against other US utilities.

"An attacker could break all of that at once. It would be like New Orleans after Hurricane Katrina — minus the National Guard rescue," he said. "It would be impossible to engage in civilian life. That is the vision of cyber-war."

This year has been a fraught one for international relations on the cybersecurity front, with the US accusing her rivals China and Russia of sponsoring cyber attacks on its citizens and corporations through proxy groups.

In May an American grand jury indicted five Chinese officials for stealing trade secrets through cyber espionage, the symbolic gesture prompting furious denials from China.

"We need to face up to the prospect that cyber war, when it comes, will be ugly and will harm civilians in a dramatic fashion," Baker added.