North Korea has nuclear-armed missiles and satellites potentially capable of electromagnetic pulse (EMP) attack. EMP is considered by many the most politically acceptable use of a nuclear weapon, because the high-altitude detonation (above 30 kilometers) produces no blast, thermal, or radioactive fallout effects harmful to people.

EMP itself is harmless to people, destroying only electronics. But by destroying electric grids and other life-sustaining critical infrastructures, the indirect effects of EMP can kill far more people in the long-run than nuclear blasting a city.

In this scenario, North Korea makes an EMP attack on Japan and South Korea to achieve its three most important foreign policy goals: reunification with South Korea, revenge upon Japan for World War II, and recognition of North Korea as a world power.

Revenge against Tokyo is a convenient rationale for someday attacking Japan. War against Japan will be necessary for the North to conquer South Korea, as Japan is an indispensable staging area for U.S. and allied forces defending South Korea.

North Korea's dictator, Kim Jong Un, is the scion of three generations of totalitarian rule, a megalomaniac and ruthless murderer described by state media as a demigod having supernatural powers.

Kim’s strategy is to sever U.S. security guarantees to South Korea and Japan by raising the stakes too high—raising the specter of nuclear war—and through "nuclear diplomacy" to cow the U.S. and its allies into submission. 

In this scenario, North Korea detonates a nuclear weapon at 96 kilometers HOB (height of burst) over Tokyo. The EMP field extends from the Japanese capital to a radius of 1,080 kilometers, covering all of Japan's major home islands. 

Virtually all of Japan's major military bases and seaports are covered by the EMP field, rendering them inoperable. Traffic control towers and systems are damaged and blacked-out stopping air and rail traffic. Highways are jammed with stalled vehicles. Communications systems are damaged or destroyed or in blackout.

Worse, Japan's population of 126 million people is at risk because suddenly there is no running water or food coming into the cities. EMP induced industrial accidents are happening everywhere. Gas pipelines are exploding and turning into firestorms in towns and cities. Refineries and chemical plants are exploding, releasing toxic clouds and poisonous spills. Tokyo knows from the experience of Fukushima that as the nationwide blackout becomes protracted, within days Japan's nuclear reactors will exhaust their emergency power supplies and begin exploding, contaminating the home islands with radioactivity. 

As a consequence of the EMP attack, Japan's critical infrastructures are paralyzed and incapable of transporting U.S. forces to aid South Korea. Indeed, with Japan's survival at risk, Tokyo would probably oppose any effort to help South Korea by U.S. forces staging from Japan, fearing another North Korean EMP attack. 

The EMP field also covers the eastern half of South Korea, including the vital seaport of Busan (the key to South Korea's survival and U.S. victory in the last Korean War). All the eastern coastal seaports, and all military bases and airfields in the eastern half of South Korea (nearest Japan) are under the EMP field. 

The EMP field does not extend to North Korea.

Left uncovered by the EMP field are the western half of South Korea, including Seoul, the capital, and the major highway systems radiating around and from Seoul southward—the best invasion routes. Stalled traffic from the EMP will not be blocking Seoul or the highways.

U.S. and South Korean forces covering the Demilitarized Zone (DMZ) will not be covered by the EMP field. The EMP field, in their immediate rear area, will cause cascading failures of the electric grid throughout the DMZ and the entirety of South Korea. 

Thus, even those U.S. and South Korean forces not covered by the EMP field will be in a paralyzing protracted blackout that will cripple or deny allied forces communications, transportation, food and water, supplies and reinforcements from South Korean bases or from overseas.

The EMP attack creates conditions for North Korea's conquest of South Korea that are ideal.

North Korean armor and infantry pours across the DMZ, thrusting through and around Seoul and down the coastal highways, flanking U.S. and allied forces paralyzed by EMP and unable to maneuver.

U.S. nuclear missiles and bombers start blasting North Korea’s nuclear forces and underground bunkers where the Dear Leader may be hiding. Now Kim Jong-Un knows he has miscalculated. The U.S. is no paper tiger.

In a final act of vengeance, Kim detonates the Super-EMP warhead in his KMS-4 satellite, blacking-out the United States. 

Airliners crash. Communications and transportation stop. Natural gas pipelines explode, causing firestorms in cities. In 7 days, 100 U.S. nuclear reactors go Fukushima. In a year, most Americans are dead from starvation.

The United States, Japan, South Korea, and North Korea are in ruins.

Russia and China are the winners.

Mr. President, harden the U.S. electrical grid to defend against an EMP attack, and shoot down those North Korean satellites!

Dr. Peter Vincent Pry is chief of staff of the Congressional EMP Commission. He served on the staff of the House Armed Services Committee and at the CIA.