For nearly two decades, Iranian military planners have experimented with the possibility of launching an electromagnetic-pulse (EMP) attack that could instantaneously disable electronic systems across the U.S. and lead to nationwide disaster. The nuclear deal, write James Woolsey and Peter Pry, will pave the way to such an attack:
Iran can threaten the existence of the United States by making an EMP attack using a single nuclear weapon. It may obtain one, relatively easily, by cheating in the use of the nuclear infrastructure permitted them under the agreement. U.S. intelligence cannot meet the impossibly high standard of assuring that Iran cannot acquire a single nuclear weapon and, given the regime’s existing nuclear infrastructure, cannot with absolute certainty guarantee that Iran does not already have one.
A single nuclear weapon detonated at high altitude over the United States would generate an EMP that could black out the electric grid and other life-sustaining, critical infrastructures such as communications, transportation, banking and finance, food, and water. The Congressional EMP Commission estimated a nationwide blackout lasting one year could kill anywhere from two of every three Americans (by a low estimate) up to nine of ten Americans by starvation and social disruption.
[A]n Iranian military textbook . . . describes nuclear EMP effects in detail. In more than twenty passages, it advocates an EMP attack to defeat an adversary decisively. The [book also] advocates a revolutionary new way of warfare that combines coordinated attacks by nuclear and non-nuclear EMP weapons [with] physical and cyberattacks against electric grids to black out, and cause the collapse of, entire nations. . . .
The Congressional EMP Commission found that Iran has practiced launching missiles and fusing warheads for high-altitude EMP attack, including off a freighter. Iran has apparently practiced surprise EMP attacks, orbiting satellites on south-polar trajectories to evade U.S. radars and missile defenses. . . . A single nuclear weapon would complete the list of requirements.