This year, we might get a less traditional view during the Independence Day celebration: The sun recently produced solar flares that could cause a northern-lights effect visible from the earth and disrupt electronic communications.

This is a reminder that severe solar activity would be devastating. While solar weather can cause severe damage to a power grid and other electronic devices, the United States remains largely unprotected from its effects.

Space weather offers a preview of what would happen if the U.S. were attacked by an electromagnetic pulse (EMP) weapon. An EMP is a high-intensity burst of electromagnetic energy caused by the rapid acceleration of charged particles. As shown in Heritage’s documentary 33 Minutes, a nuclear weapon detonated at a high altitude would send the U.S. back to the 18th century. Cars would not start, all power would go off, computers and all other electronic equipment would not work, and planes would fall from the sky.

The congressionally mandated EMP Commission Report stated that an EMP “has the capability to produce significant damage to critical infrastructures and thus to the very fabric of US society, as well as to the ability of the United States and Western nations to project influence and military power.”

There are steps the U.S. government can take to protect the country from the consequences of these events. It should harden its critical infrastructure and develop a national plan to respond effectively to EMP emergencies. This would involve educating federal, state, and local officials along with the public about the risks and response options. In addition, the U.S. should invest in layered missile defense architecture to protect its territory against the threat of an EMP attack delivered by short- or long-range ballistic missiles.

The threat of space weather and EMP deserves proper planning and robust defenses.