Here’s What Would Happen If US Nuked North Korea
Above photo: Detonation of Ivy Mike, the world’s first thermonuclear weapon (National Nuclear Security Administration, 1952)
When you have a hammer, everything looks like a nail. Maybe this is why so many Americans wonder why they can’t just nuke a country posing a risk to their security. With an arsenal of some 6,800 operational and precisely engineered warheads, it seems almost too appealing to end all your worries with the push of a button. But there’s a good reason why our nuclear posture isn’t determined by trigger-happy civilians eager to immolate enemy nations in radioactive hellfire. More than two decades of not having to think about nuclear annihilation seem to have created a bizarrely casual attitude about the, well, for lack of a better word, fallout from using nukes.
Maybe this is why Trump has been psychotically cavalier about the notion of starting a nuclear war lately. It’s as if we’ve time-traveled to 1950 when the Korean War gave Douglas MacArthur the idea to nuke China in response for intervening with his forces, an idea that was rebuffed as not to invite Russian use of nuclear weapons in otherwise conventional conflicts, and ultimately cost the general his job after he went rogue and tried to defy Truman’s orders on the subject. Just like MacArthur, Trump seems unable to grasp the real world consequences of deploying humanity’s deadliest invention on a whim.
Nuclear weapons are not just big bombs that create huge fireballs and level a large territory. On top of the terrifying geopolitical implications, they come with some very nasty side-effects that are impossible to contain, especially if they’re ever used in bulk. But before we get into the details, a primer on how these weapons work and how this influences fallout seems in order. We’ll use the American W88 warhead as our example, the 450 kiloton thermonuclear device on standby today, and seemingly a close analog to North Korea’s last unveiled design according to the experts.
The W88 is an implementation of the Teller-Ulam design, named after the duo of academics who came up with the concept for the thermonuclear warheads we know and fear today, though their collaboration wasn’t exactly friendly. The overall idea is to put the core of a fission device, much like the ones that leveled Hiroshima and Nagasaki, and use the heat, radiation, and pressure of the initial fission blast to trigger the ignition of a radioactive spark plug which would fuse two isotopes of hydrogen into helium. The fission device would be the primary, logically making the fuel for the subsequent fusion reaction the secondary, which is how they’re referred to in all designs.
While the isotopes in question — deuterium, distilled from water, and tritium, created when the neutrons from the fission blast bombard lithium-6 in the warhead — are the same for every thermonuclear design, the W88 features a rather interesting, and very relevant twist. Most of its explosive yield comes from its unusual, egg-shaped fission primary, meant to help miniaturize the warhead so multiple bombs could be fitted on a single missile. This way, it could be delivered using MIRVs, or Multiple Independent Reentry Vehicles, making attempts to intercept it by an enemy state fiendishly difficult.
Incidentally, the oblong fission primary is why the North Korean design was shaped like a peanut, and why experts are worried that miniaturization isn’t far off. Americans used the same design for the same reason and saw it used by China also for enabling miniaturization of its warheads. But this makes the W88 and devices like it “dirtier” when they detonate, and this is going to be really important because the fallout plays a big role in what happens after a bombardment stops, which is in part why nuclear powers tend to maintain a wide variety of bombs suited for different tasks.
Some devices, like the W70–3, were intended to be low fallout to allow their tactical use during conventional wars. Other designs, like the American B41 and the Russian RDS-220, far better known as the Tsar Bomb, elaborated on the Teller-Ulam design and had three stages. They could have “clean” tertiary stages which used the energy of the first two stages to trigger an additional fusion reaction, or “dirty” fissionable materials that boosted the yield for the primary and secondary. Fusion produces much lighter, more stable elements than fission which give off far less radiation, but fission relies on belching radioactive particles, so the more of your yield comes from fusion, the cleaner your bomb is, and vice versa.
The fallout of a three stage nuke could be further reduced with a lead tamper between the primary and the other stages, or boosted with the typical and far more powerful uranium-238 one. In a nightmare scenario that makes experts shudder, the primaries could be encased with cobalt, creating some very, very nasty radioactive byproducts that would blight a wide area for decades rather than months. It’s known as a “salted bomb” and widely considered too tricky and suicidally insane to build, which is why it remains theoretical.
Ideally, the cleanest weapons of mass destruction we could build would be a pure fusion device — which we only have the foggiest theoretical idea of how to create, much less miniaturize and put on a missile — or an antimatter bomb, which would convert every atom of its fuel into gamma rays and is far simpler to create. However, the process of manufacturing enough antimatter would take so much time and money, it would be the most expensive weapon in all of history at 100,000 years and at least $100 trillion per warhead, barring a revolutionary discovery in particle physics.
So, now that you’re an expert in how nukes work, let’s consider one scenario in which, oh, say just for the sake of speculation, the U.S. launches 100 or so missiles at North Korea. We might not launch nearly that many nukes if we actually decided to do this and different strategic targets would need to be hit with different types of missiles and warheads, and they’re likely going to be hit with multiple warheads to make sure they’re damaged beyond all repair. Plus, the president has full autonomy over the nuclear football and in theory, could order as many strikes as he feels necessary. But 100 missiles is a large, round number and is a common enough refrain to consider.
They’ll take about 35 to 45 minutes to hit all their targets and it’s extremely likely that every one will go off exactly as expected since American nukes are precisely engineered and thoroughly reliable. After a hundred mushroom clouds will dissipate, some really, really bad things will start to happen at a fairly rapid pace. North Korea will be in ruins, and while it won’t glow with radiation, its territory will be lethal to any living thing. A smaller strike will leave patches of relatively safe territory in the mountainous terrain, but as North Korea occupies almost exactly the same land area as Pennsylvania, there’s not much room to hide, so a stiff breeze can cover survivors under a fallout cloud very quickly.
After the initial burst of gamma rays created by the blasts, the heavy elements from the fission primary, the uranium spark plug, casing, and tamper, will mix with the air currents generated by the heat of the nuclear fireballs and come down as a black, sticky rain after about 40 minutes to an hour. This is exactly what happened in Hiroshima, but that was one explosion. The combined soot and heat from 100 blasts would be like a massive volcanic eruption, except it would also be far, far deadlier. Depending on the weather conditions, it’s not out of the question to see black rainstorms across the entire region.
And herein lays the problem. The affected region would include our frenemy China, our rival Russia, and our allies Japan and South Korea. Radioactive particles will spread across the Northern Hemisphere, ending up in Hawaii, Alaska, Washington, Oregon, California, and the Canadian Pacific Coast. The fish many nations around the Pacific Rim rely on for food would be killed or contaminated. Tens of millions will be poisoned or sickened, and even several generations down the line, there will be numerous birth defects and cases of aggressive cancers as lower intensity fallout takes its toll.
Even worse, about 100 W88 detonations, or bombs like this, are more than enough to start nuclear winter. Yes, that’s right, things are about to get worse. As the radioactive soot travels across the world, carried by currents high in the atmosphere, it begins to blot out the sun, cooling the planet. While this could temporarily stop global warming, it will also collapse countless food chains, and guarantee failure of harvests blighted with the unstable isotopes raining from the sky, then denied sunlight, even after replanting and disposing of the contaminated soil to start rebuilding.
Our enemies may be dead and dying, but we and our allies will also have to deal with the fallout, the nuclear winter’s decade or so of hungry years, and the long term residual effects of being irradiated. Over 371.8 million people live in the region in question, and a tens of millions more could also feel the effects of the fallout and food shortages. It’s hard to estimate how many will succumb because that depends on numerous factors like the wind, weather, and the timing and precise location of the explosions, but it will certainly be in the low eight figures at the very least.
A smaller strike would stave off nuclear winter and lessen the possible long term casualties from the disruption of the food supplies. However, given the population density of the region, the death toll would still be in the tens of millions and spread to our allies. There could still be regional climactic and weather disruptions, and even though they would disappear within years rather than decades, they could still cause enough collateral damage to be extremely troublesome for recovery efforts. We’d be in uncharted territory and all we’d have to go by would be theoretical models.
What we can say for sure is that our allies in the region will be the hardest hit while nations with which we don’t have the best relations will suffer the side-effects of the bombing and be very unhappy about. Northeast China, which borders North Korea, is home to almost 165 million people. South Korea has over 52 million people in its territory and its capital will feel the direct brunt of the black rain and gamma rays from Pyongyang’s destruction. Japan’s will be hit with the dangerous soot from the blasts as well.
It’s very likely that Seoul will not be looking at Washington as an ally for the next few generations, and neither will Tokyo. Beijing and Moscow would be seething over their citizens being irradiated and threatening to launch their missiles at America’s West Coast’s citizens, who would now be very likely to suffer a number of long term effects from the debris that will travel across the ocean on a much larger scale than it did from Hiroshima and Nagasaki. So, to borrow the most popular saying of 2017, it will be a shit show, with a decent chance of World War 3 erupting in the aftermath.
Keep that in mind next time a certain cable news addicted senior citizen with an unhealthy interest in why we can’t just use nuclear weapons to make our problems go away gets in a Twitter beef with someone who actually has nukes and very little to lose if attacked.
We are not untouchable, we will be inviting another global war if we strike first, and even if we could avoid retaliation by a combination of missile defense and extreme diplomacy, the fallout from a massive nuclear volley will come back to haunt us over the medium and long term. So unless you have a luxury space habitat, or another world you can jump to after you press that button, nukes are the last resort of a nation with its back against the wall, not a weapon of choice, which is why this is the doctrine of just about every member of the nuclear club.