At a prior hearing, on July 22, 2004, panel members from the EMP commission stated that as U.S. military weapons and control systems become more complex, and as portions of the military's administrative communications systems continue to rely on the U.S. civilian infrastructure for support, they may be increasingly vulnerable to the effects of EMP. Volume 3 is an unclassified Assessment of the U.S. Critical Infrastructure. Testimony at the 2004 hearing included questions such as (1) how would the United States respond to a limited HEMP attack against the U.S. homeland or against U.S. forces, where there is loss of technology, but no directly caused loss of life; (2) does the current lack of U.S. preparedness invite adversaries to plan and attempt a HEMP attack; and (3) are the long-term effects of a successful HEMP attack, leading to possible widespread starvation and population reduction, potentially more devastating to the U.S. homeland than an attack by surface nuclear weapons? In the past, the threat of mutually assured destruction provided a lasting deterrent against the exchange of multiple high-yield nuclear warheads. However, a single, low-yield nuclear explosion high above the United States, or over a battlefield, can produce a large-scale, high-altitude EMP effect resulting in widespread loss of electronics, but possibly without direct fatalities. Such a perceived lower risk of assured destruction by the United States, and widespread knowledge about the vulnerability of U.S. civilian and military computers to the effects of an EMP attack, could actually create a new incentive for other countries or terrorist groups to develop, or perhaps purchase, a nuclear capability. High-Power Microwave (HPM) electromagnetic energy can be produced as a near-instantaneous pulse created through special electrical equipment that transforms battery power, or powerful chemical reaction or explosion, into intense microwaves that are also very damaging to electronics, but within a much smaller area. Policy Analysis

		Preparedness

What is the United States doing to protect critical infrastructure systems against the threat of electromagnetic pulse? Does knowledge of this vulnerability, combined with the proliferation of nuclear technology, provide a new incentive for potential adversaries to develop or acquire a nuclear weapons capability? It is difficult to assess the threat of a terrorist organization possibly using a smaller-scale HPM weapon against the United States critical infrastructure.
Electromagnetic Pulse (EMP) is an instantaneous, intense energy field that can overload or disrupt at a distance numerous electrical systems and high technology microcircuits, which are especially sensitive to power surges. A large scale EMP effect can be produced by a single nuclear explosion detonated high in the atmosphere. This method is referred to as High-Altitude EMP (HEMP). A similar, smaller-scale EMP effect can be created using non-nuclear devices with powerful batteries or reactive chemicals. This method is called High Power Microwave (HPM). Several nations, including reported sponsors of terrorism, may currently have a capability to use EMP as a weapon for cyber warfare or cyber terrorism to disrupt communications and other parts of the U.S. critical infrastructure. Also, some equipment and weapons used by the U.S. military may be vulnerable to the effects of EMP.
The threat of an EMP attack against the United States is hard to assess, but some observers indicate that it is growing along with worldwide access to newer technologies and the proliferation of nuclear weapons. In the past, the threat of mutually assured destruction provided a lasting deterrent against the exchange of multiple high-yield nuclear warheads. However, now even a single, low-yield nuclear explosion high above the United States, or over a battlefield, can produce a large-scale EMP effect that could result in a widespread loss of electronics, but no direct fatalities, and may not necessarily evoke a large nuclear retaliatory strike by the U.S. military. This, coupled with published articles discussing the vulnerability of U.S. critical infrastructure control systems, and some U.S. military battlefield systems to the effects of EMP, may create a new incentive for other countries to rapidly develop or acquire a nuclear capability.
Policy issues raised by this threat include (1) what is the United States doing to protect civilian critical infrastructure systems against the threat of EMP, (2) could the U.S. military be affected if an EMP attack is directed against the U.S. civilian infrastructure, (3) are other nations now encouraged by U.S. vulnerabilities to develop or acquire nuclear weapons, and (4) how likely are terrorist organizations to launch a smaller-scale EMP attack against the United States?
This report will be updated as events warrant.