An electromagnetic pulse (EMP) is a high-frequency burst of electromagnetic energy caused by the rapid acceleration of changed particles. A catastrophic EMP would cause the collapse of critical civilian infrastructures such as the power grid, telecommunications, transportation, banking, finance, food and water systems across the entire continental United States—infrastructures that are vital to the sustenance of our modern society and the survival of its citizens.
An EMP event can occur naturally from a great geomagnetic storm, or it can be man-made through the use of a single, crude nuclear weapon delivered by a primitive missile, and the effects would be virtually identical.