Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. ensure an effective homeland defense and homeland security effort should understand the implications of a successful HEMP attack on the United States, the factors that influence the probability of an attack, and continuously seek innovative ways to prevent such an attack from ever occurring, and simultaneously, to prepare for it, if preventative efforts should fail.This paper describes what an electromagnetic pulse (EMP) is and how a nuclear weapon creates a HEMP. Next, a brief description of the effect of a HEMP attack on electrical and electronic systems is followed by an overview of the implications of the failure of these systems on the nation's critical infrastructure and elements of national power. A discussion of the risks of such an attack caused by nuclear and ballistic missile proliferation will be followed by an overview of the on-going contributions of the existing National Security Strategy and National Strategy for Homeland Security to prevent and prepare for a HEMP attack. This paper will conclude with some broad recommendations to strengthen the United States' capabilities to prevent, and simultaneously prepare to mitigate and recover from, the effects of this ultimate form of asymmetric attack.iv v