Few weapons are as scary as those that exist only in our minds.
A few years ago when the Republican Party released its platform to the public in the run-up to its national convention at the tail end of a section titled “America Resurgent,” GOP leaders detailed what they felt is a looming threat of America — electromagnetic pulses.
“A single nuclear weapon detonated at high altitude over this country would collapse our electrical grid and other critical infrastructures and endanger the lives of millions,” the platform stated. “With North Korea in possession of nuclear missiles and Iran close to having them, an EMP is no longer a theoretical concern — it is a real threat.”
But it’s not.
Recommended: Stealth vs. North Korea’s Air Defenses: Who Wins?
The problem with fear over electromagnetic weapons is that it forgets two simple facts. First, generating enough juice to cause a significant amount of damage is really hard. Second, a country dealing with busted electronics after an EMP assault is a country fighting a nuclear war.
(This first appeared in WarIsBoring back in 2016.)
“EMP is the new test case of seriousness in national security,” cyber security expert Peter W. Singer tweeted after reading the platform. “But not in the way advocates not in on the joke think.”
I reached out to Singer and, after a brief pause to make sure I was serious, he pounced. “There’s this irony of the people who think it’s serious not realizing that they’re the joke,” he explained. “When you walk through the actual scenarios of use, it doesn’t pass the logic test.”
An electromagnetic pulse following a nuclear blast is a real thing. The problem is that the process of creating an EMP big enough without the devastation of a nuclear warhead is expensive, absurd and not worth the effort. That’s if it even works.
For that, we can’t recommend enough a 2010 series of articles in The Space Review by Yousaf M. Butt, a physicist currently serving as a foreign affairs officer in the State Department’s Space and Advanced Technology office.
“For a large device (greater than 100 kilotons) …. the whole region on the Earth’s surface which is within line-of-sight to the high-altitude explosion will experience the EMP pulse,” he wrote.
Which sounds scary, but there are several important caveats. The higher you detonate a nuclear device, the greater the blast radius. However, the effect of the EMP will be less. Likewise, the smaller the explosive yield, the smaller the EMP and the closer the blast will need to be to the ground to be effective.
Finding that detonation sweet-spot in the Earth’s atmosphere will take countless tests … which no one has done.
The blast Butt described above, one that knocks out the entire electrical system on roughly half the Earth’s surface, could only come from a high-yield thermonuclear warhead attached to an ICBM. So, engaging in the fantasist view, a nuke from Russia or China.
Setting aside the geopolitical gymnastics that must occur to lead to that kind of exchange, if a foreign power detonated a 100 or more kiloton in an electromagnetic attack on America, then the world is at war and there’s little strategic benefit for the aggressor to not just go ahead and nuke a city.
“It doesn’t mean it can’t happen,” Singer told me. “But if the other side is using EMPs we’re moving into thermonuclear war.”
“A weapon of mass destruction is preferable to a weapon of mass disruption,” Butt explained. “A state would be highly unlikely to launch an EMP strike from their own territory because the rocket could be traced to the country of origin and would probably result in nuclear or massive conventional retaliation by the U.S.”
Let’s say the EMP does go off in space above North America. According to the worst case scenario, the attack would fry the Pentagon’s electronics, leaving the U.S. military unable to retaliate.
However, we don’t know what the effects of an EMP might be. Studies conducted by both the Soviet Union and the United States during the Cold War produced dramatically different results every time.
An electromagnetic pulse is a highly unpredictable side effect of a predictably horrifying weapon. “It’s not a weapon we’ve seen past use of. Ever. Literally ever. Nor tests of,” Singer said.
Some countries have attempted to weaponize EMPs in fits and starts, but it remains a byproduct of other weapons systems, including cruise missiles as well as nukes. The idea of North Korea or Iran using a small-yield nuclear device in low atmosphere fails for the same reasons. North Korea can barely manage to cobble together a crude one-kiloton bomb, let alone a device large enough to do significant damage to U.S. infrastructure.