"In little more than a generation, the Internet has become the substrate of the global economy and governance worldwide. Several billion more human users will be added in the next decade, as will tens of billions of devices, ranging from thermostats to industrial control systems (the 'Internet of Things'). All of this burgeoning interdependence implies vulnerabilities that governments and non-governmental actors can exploit. At the same time, we are only beginning to come to terms with the national-security implications of this. Strategic studies of the cyber domain resemble nuclear strategy in the 1950s: analysts are still not clear about the meaning of offense, defense, deterrence, escalation, norms, and arms control."