General Michael Hayden, the longest-serving head of the NSA and a former director of the CIA, has been warning of the dangers of cyber-war on the internet and how the military is preparing for online war.

During his keynote presentation at Black Hat last week he said that traditionally the US military had operated in four spheres: ground, air, water and space. The internet is now the fifth domain, and was the first man-made location for warfare, since the others were made by God.
"God did a better a job,” he said.
The problem with the internet was that it has no real security systems in place. Everything online is in the attacker’s favour, while there is virtually nothing for the defending team, he said.
Hayden expressed irritation at the ease with which some people bandied around the term 'cyber-war', saying the term was overused. Stealing documents is not cyber-war he said, it’s espionage that is as old as the nation state.
An actual cyber-war could have dramatic real-world fallout, he said, adding that the leading nations should band together to outlaw online warfare, for fear that it could cause immense damage.
One of the problems of online attacks is that you often can’t determine who is carrying out the attacks, making it difficult to bring the perpetrators to justice, he said. Much more work was needed in 'beefing up' both defence and attacking skills.