From the Heritage Foundation.

Excerpt:

[Tuesday] night at The Republican National Security Debate, hosted on CNN by The Heritage Foundation and the American Enterprise Institute, an electromagnetic pulse attack (EMP) was mentioned as one of the most important national security issues that is not discussed often. This is true. Despite the gravity of the threat, the United States remains unprotected from the effects of an EMP.

An EMP is a high-intensity burst of electromagnetic energy caused by a rapid acceleration of charged particles. The EMP would disrupt all electronic devices within its zone of impact. It would burn circuits and immobilize electronic components and systems. It addition, the EMP would flow through electricity transmission lines and would damage distribution centers and power lines.

Detonating a singular nuclear weapon at a high altitude can create an EMP large enough to envelop the entire continental United States. The nuclear weapon could be delivered by a long-range ballistic missile from Iran, China, Russia, or North Korea. Even a short-range nuclear-tipped missile launched off of the U.S. shore could cause a devastating EMP effect.

[…]The effects of an EMP on today’s society would be even more devastating. According to Heritage’s James Carafano, “communications would collapse, transportation would halt, and electrical power would simply be nonexistent. Not even a global humanitarian effort would be enough to keep hundreds of millions of Americans from death by starvation, exposure, or lack of medicine.”

There are some simple steps that can be taken to prevent against the crippling effects of an EMP attack. First, the U.S. needs to build and adequately fund a robust missile defense system composed of Aegis ballistic missile capable ships, and Aegis Ashore, the land-based ballistic missile component. Second, both the public and private sectors should harden vital infrastructure to make it more resilient and resistant to the EMP—to hedge against an attack or prepare for a solar flare. Third, the U.S. should develop a national plan to respond to EMP emergencies. This would involve educating federal, state, and local officials along with the public about the risks and response options.

In case you missed the debate, you can watch the whole thing here: (and you should – it was awesome)

For the record, the consensus in the Republican debate was that there were “under-the-radar” threats, in addition to threats from Iran, Pakistan, North Korea, China, etc. These were: 1) Cyber attacks like the recent attacks that originated in China, 2) EMP attacks such as I described above and 3) terrorist attacks coordinated with actors in Latin America and South America that exploit our porous southern border.