Instead the attacks are launched by computer hackers. Digital spy rings. Information thieves. Cyberarmies of kids, criminals, terrorists - some backed by nation states.

In the Us there Is a growing fear that they pose a massive threat to national security, and a conviction that the world's military superpower must prepare for the fight ahead. 

At stake: Crucial national infrastructure, high value commercial secrets, tens of billions of dollars in defence contracts, as well as values like privacy and freedom of expression.