Rethinking Passive Defense
For consideration by the U.S. Army Chemical Corps - defending against drones
So stay with me for a second. Everyone is talking of course about the Ukrainian success with using drones as deep theater attack weapons against Russian strategic bombers and other planes. First of all, good on the Ukranian army, excellent tactic, may not win the war but it’s certainly a shock to the senses to many. But looking at this operation and extrapolating upon the potential impact of such an attack on U.S. forces, it made me wonder as to the possibilities of applying the CBRN defense, or passive defense, construct to protective measures against swarms of explosive-laden drones. The Army Chemical Corps has been trying for literately decades to get people to view them as CBRNe specialists, despite the lack of any real similarity of CBRN defense to defending against the use of high-yield explosives. Yes, yes, I know, it’s all about the desire for a common response plan, and in particular, domestic terrorism response, not going to get into that right now.1
I am not talking about counter-UAS concepts and capabilities. In my mind, there’s a distinction here similar to countering WMD and CBRN defense, in that counter-UAS concepts are largely about offensive capabilities used to scramble or deny an airspace of adversarial drones. There are no specific defensive measures that individuals take from drones other than maybe hiding from them. Could we not develop a concept for what to do when those drones, particularly mass drone waves, penetrate one’s perimeter and pose an immediate threat to service members? Maybe such a concept already exists and I’m just wasting my time. But I think there might be something that the Chemical Corps can offer, in particular since the majority of DoD personnel don’t believe in countering weapons of mass destruction anymore.
Here’s my theory. In CBRN defense, we’re taught to assess/avoid CBRN agent contamination, protect against the effects of CBRN agents, and respond/recover from contamination associated with CBRN agents.2 The exact names of these principals vary from time to time, as the mood hits particular leaders at the CBRN School, but it’s been pretty consistent since my time in the military, at least since the late 1980s. It’s a very technically focused approach to mitigating large-scale area CBRN attacks, allowing for a degree of individual risk proportional to the need to conduct combat operations. No one (well, mostly no one) is trying for OSHA-level standards of protection against these agents. Can this approach be generally applicable to a passive defense concept against drone swarms?
(U.S. Army photo by Staff Sgt. Godot G. Galgano, 1st Theater Sustainment Command Public Affairs, 2021)
To start, this is not the first time that the term “passive defense” has been appropriated for a new threat. During the Cold War, passive defense was a concept to protect the civilian populace from Soviet bombers that had penetrated U.S. air space.3 This would include radar installations for tracking the threat, air raid sirens for alerting the populace, civil defense shelters to protect the citizens, and rescue and recovery services. “Active defense” included fighter interceptor wings and air defense missile sites. When the Defense Counterproliferation Initiative came about in the 1990s, the Air Force was fundamental in developing terms for this new area. This is when the terms “passive defense” and “active defense” moved from being Cold War terms to combating WMD terms.
People have already made comparisons between weapons of mass destruction and drone swarms. The idea is there, but we just haven’t figured out the right concept to defend against them. If applied to mitigating the threat of mass drone strikes, what would this passive defense concept look like? We can already see that counter-drone concepts are really focused on active defense right now, to include early detection and warning, identification and tracking, and engaging and defeating the hostile target with kinetic or non-kinetic effects. There’s no mention that I can see as to passive protective measures necessary if the drone swarm slips through these protective measures. Can we, then, identify a theoretical construct of passive defense against drone swarms?
I’m going to use the old-style terms for passive/CBRN defense, because I’m more comfortable with those terms and because I think the CBRN defense community screwed up changed the terms because, reasons (like taking the opportunity to come up with new words in the next draft field manuals so you have something for your annual assessment). We had capability areas that included point/standoff detection, hazard and warning systems, individual protective equipment, collective protection shelters, and decontamination devices. For obvious reasons, I’m going to have to use the “new” term of respond/recover instead of decontamination. Medical capabilities include diagnostics (often included under detection), pre-treatments and vaccines (an aspect of individual protection), and post-treatments and therapeutics (part of respond/recovery), but I don’t think there would be a special medical capability area for a passive defense concept against drones.
Developing a point/standoff detection system for drone swarms would actually be the toughest part of this concept, in that I’m not familiar with specific technologies that could perform this function. Back in WW1, the Army had “gas sentries” -- soldiers who were supposed to be alert for signs and symptoms of gas attacks and to sound the alarm for their unit. In the near term, I would suggest that “point detection” would involve designated individuals with optical sensors watching for drones and pinning the information on digital maps. Some first-person shooter games have this capability to “spot” and “track” enemy targets; maybe this could be replicated with smart goggles and an interface to combat maps. This could be supplemented by RF sensors placed around the unit position. The standoff detector would need to be worked out. I would expect some kind of high-resolution radar packaged in a portable function so as to deploy it when the unit stops. This might be something that is only deployed on reconnaissance vehicles or around military bases, adding one more function on to its list of things to look for. This technology is out there, even as I’m not sure how it would be developed and deployed.
There probably already is a hazard and warning software capability for integrating information about hostile drones into digital maps. I don’t know what the state of the art is these days for battlefield situational awareness, but this is probably just a challenge in as much as connecting the detectors to the map and creating a blue/red awareness of the drone threat. I think there would be some value in training operators (or AI?) to recognize drone swarms as something different than birds flying in a group and then communicating that to individuals within a certain area of responsibility. We don’t do this well with CBRN hazards because it’s a matter of getting basic hazard information quickly to individuals downwind of the attack as opposed to getting high grade resolution of the hazard as a result of local weather, height of burst, amount of the hazard involved, etc etc.
Individual protection is the easiest part of this concept. Service members on the ground already have concerns about kinetic weapons and explosives, so it’s not like they are going to have to carry new Kevlar vests or new helmets. The key to individual protection is to develop capabilities that can make the individual less visible on the battlefield. This isn’t just the use of camouflage nets but also masking any evidence that an individual is in a fighting position, such as policing up garbage or hiding ammunition crates. Collective protection similarly would use existing technologies to mask and harden vehicles, vans, and shelters from observation, and in addition, prepare ancillary positions and camouflage any communications systems. The good news for the Chemical Corps is that smoke obscuration missions are back, baby!!
(source: Australian Army, “How to Protect Yourself from Enemy Drones”)
From personal experience, I can tell you that the Chemical Corps has a great capability to smoke out square kilometers of territory. I once used smoke pots to obscure a MOUT training site at Fort Benning, although the battalion commander wasn’t thrilled with the result (too much smoke for him to see the troop action). The soldiers loved it though. But over the past 20 years, smoke and obscuration has not been a big part of the Chemical Corps, and probably largely remains in the Reserves. Big Army didn’t see the value of such systems because their maneuver units move so quickly and because they expect air superiority to protect against airborne threats. Time to bring it back.
Response and recovery operations are not a challenge in a passive defense concept for UAS because it would be the same process as recovering from a local small-unit attack. I would envision a need to emphasize logistics and to preposition consumables like body armor, camo nets, all of the supplies that might get used up when a unit has to displace and move on the battlefield to a new location. Some of that stuff would be survivable, but if it’s a large drone swarm, resupply would be something to keep an eye on. Speaking of survivability, the ability to mitigate damage through increasing the survivability of vehicles, vans, and shelters would be a really good idea. Again, it’s hard to push CBRN survivability in most conventional military hardware because it involves using special materials and testing the effectiveness of decontaminates before a piece of military hardware is fielded. A lot of program managers don’t want to take the time and funding to do CBRN survivability right, and it gets waived out of the acquisition process. Bringing a survivability aspect into any new vehicles, vans, or shelters for the purposes of hardening them prior to deployment would probably be a good thing. We should avoid “The Pentagon Wars” process of testing, however.
The value of this approach is that we don’t necessarily need to spend hundreds of billions on an “Iron Dome” system designed to defeat UAS/drone swarms moving against military forces in the field. This passive defense concept supports masking military operations in an environment where if you see something, you can kill it within a short timeframe. This concept could be applied to military facilities as well, although with some obvious modifications. I don’t expect that individuals on a CONUS military base would have gear for individual protective measures or even practice it regularly to maintain such skills.4
So that’s what I have for this concept. It’s a bit loose at the moment, I realize, but I am sincere in believing that our Army Chemical Corps soldiers could really cash in by using their talents and concepts to apply CBRN defense principles to “passive defense” against drone swarms. The Joint Staff should also start thinking about a larger joint strategy to meld active defenses against drones and this passive defense concept under a general counter-UAS strategy for all services. It’s not just about hardware, but hardware is always a big component of military concepts. Now we have to think hard about the future of drone warfare.
I am the very last person in the CBRN defense community to loosely use the term “CBRNe.” I don’t like the term, I don’t care for the inference that “CBRNe” and “WMD” are synonyms. They aren’t at all the same thing. I do however recognize that states and some federal agencies, in particular those in the incident response community, do use the term CBRNe and that’s for the sake of a common response plan against all potential hazards. So I’m going to take some liberties here and try out this thought experiment.
On one hand, I recognize that this is a pretty generic concept for facing any external hazard, but it is our concept, developed and implemented over 40+ years’ time.
Just to say, I understand that the concept of “civil defense” goes back further, at least to the beginning of World War 2. The phrase “passive defense” was more of a Cold War term.
We also have this issue with protecting military facilities and bases from terrorist CBRN attacks, in that no one expects (or wants) protective gear for all individuals on a base. More on that in a future post.
I think this is a really smart idea.
People often talk about the "nuclear revolution" as the defining upheaval in the 20th century. They claim that nuclear weapons created the prominence of deterrence. This is simply muddled thinking. Actually, deterrence is the result of weapons that can fly and are relatively difficult to stop. In the era before long-range flying weapons, you simply interposed your ground forces between whatever it was you valued and the enemy. Long-range flying weapons, if they are relatively hard to stop (whether because they fly very fast, they are evasive, or they attack in swarms) undermine your ability to defend.
If you can't defend against an attack, you have to deter it. Long-range flying weapons are what brought about the deterrence revolution.
In an age where EVERY target in your country is vulnerable, the ability to mask targets (putting them underground, moving them periodically, or using smoke [or perhaps materials -- for example fine metal particles -- that disrupt the drone's ability to "see" the target] to obscure the target all become the key defensive measures needed.
I think what you've written goes to the heart of the new strategic dilemma.
The CmlC got the radiological defense mission after a competition with the Signal Corps for over a decade (1944 to 1957). The Signal Corps believed it should lead the mission as it had the weather service (fallout prediction), had photographic support (film badges), and electronics (Geiger counters). The CmlC prevailed, however, in that it had a doctrine of force protection by embedding Gas sentinels in every unit of the Army with technical gadgets and reporting system that integrated with staff operations for data, predictions, and surveys needed for maneuver.
The CmlC has been in an existential doctrinal crisis for a long time. Historically the CmlC, and CWS before it, has done well taking on emergent missions. This is an area where I have some doubts.
Clearly a "Golden Dome" strategy would fail. In cybersecurity the analogy is a fortress wall with a soft defenseless interior versus a defense through-out. Traditional air defense doctrine already places the emphasis on terminal defenses. The problem with a counter UAS strategy is that it needs even greater dispersion of terminal defenses, if not a democratization of EW capabilities. And smoke & obscurants do have a significant role in counter UAS capabilities.
I can only imagine the CmlC adding counter UAS to its mission iff it it to leverage that distributed embedding of specialists within Army units, and adding UAS to existing NBC reporting. This runs counter to current EW initiatives.