Is US vulnerable to EMP attack?

An EMP event is a doomsday scenario in which a nuclear-blast-triggered electromagnetic
pulse takes down the US power grid, leading to starvation and death. 

It is a horrifying doomsday scenario: A ballistic missile is launched, setting off a nuclear explosion in the atmosphere. The blast generates electromagnetic pulses (EMPs) that could take out the nation’s electrical grid and bring civilization as we know it ''to a cold, dark halt.''

A nuclear detonation creates plenty of terrifying effects, including a blinding (and burning) flash of light, a building-toppling blast wave, an incendiary fireball, and radioactive fallout that can drift for hundreds of miles.

But there's a lesser-known consequence of a nuclear explosion that can drastically expand its damage zone: an electromagnetic pulse, or EMP.

EMPs are rapid, invisible bursts of electromagnetic energy. They occur in nature, most frequently during lightning strikes, and can disrupt or destroy nearby electronics. However, nuclear EMPs can cover an entire continent and cripple tiny circuits inside modern electronics on a massive scale. The power grid, phone and internet lines, and other infrastructure that uses metal is also prone to effects that resemble those of a devastating geomagnetic storm.

FMI