On Tactical Nuclear Weapons, a guest post by Dr. Andy Karam
One of the things we keep seeing and hearing in the news is that Russia has threatened to use tactical nuclear weapons against Ukraine…but nobody has really explained what in the world a “tactical” nuclear weapon is. A short way to think about it is that strategy is what helps a country to win a war – tactics are what help a general to win a battle.
For instance – if your opponent has nuclear weapons, then you might decide to try to take out their nuclear weapons before the things can be used to keep your opponent from launching them against you. That’s a strategic decision – if your opponent loses their nukes but you still have yours then you’re much more likely to win the war. But here’s the thing – your enemy’s missile silos are a long way away and they’re made of reinforced concrete and likely buried underground. That means you’re going to have to use missiles to drop your weapons on them, and they’ll have to have a high enough yield to destroy hardened missile silos.
On the other hand, if all you want to do is to destroy a bridge before your enemy can cross it to attack you, you don’t need a very powerful weapon and you might be able to have it delivered by a single soldier who’s carrying it in a backpack. Destroying a bridge calls for a tactical nuke; destroying your enemy’s missiles calls for a lot of strategic nukes.
For what it’s worth – we had a few small tactical nuclear weapons on the submarine I served on in the 1980s. They were designed for self-defense – to take out an enemy submarine or surface ship(s) we simply could not get away from. They weren’t nearly powerful enough to destroy a city – but they could certainly get us out of a tight situation.
As far as radiation effects are concerned, that gets into the physics of how these weapons work. A single fission releases a fixed amount of energy (about 200 million electron volts, or 200 MeV) and will produce two radioactive fission products. You can calculate the number of fissions needed to produce, say, a 1 kT explosion…but the numbers and unit conversions aren’t very important. The important part is that the number of fissions, the amount of radiation produced, and the amount of radioactivity produced are proportional to the strength of the explosion. This means that a single 1 kT tactical nuclear weapon produces 1% of the radiation and 1% of the radioactivity of a 100 kT strategic weapon, and 10 of the small weapons will produce one tenth the radiation and radioactivity of the single larger one.
The concern with tactical nukes comes up when the opponents view them differently. If, say, Russia views tactical nuclear weapons as just very big bombs, and the US views all nuclear weapons as being equivalent, we might find Russia using a small tactical nuke to get themselves out of trouble in a battle that’s not going particularly well…and then being surprised at seeing a full-blown launch against them from the US. Would the US really launch a full-blown strategic strike in response to a single battlefield nuke? I honestly don’t know – and I’m hoping we never find out.
Listen to Dr. Karam’s Podcast on How to Survive a Nuclear Bomb Here!
Dr. Andrew Karam started his career in radiation safety with an 8-year stint in the Navy’s Nuclear Power Program. In addition to that, he has held positions in radiation safety programs, managed the radiological arm of an environmental consulting firm, and most recently, worked on radiological and nuclear emergency response planning for the NYC Health Department. He also served as a civilian scientist and subject matter expert for the NYPD’s Counterterrorism Division. He has a doctorate in Environmental Science and examined cosmic radiation exposure and how it has changed over the history of life on Earth. His most recent book is Radiological and Nuclear Terrorism, published in 2021.