Domestic Military Operations & the Homeland Defense Mission (Part One) – Forward Observer Shop

Domestic Military Operations & the Homeland Defense Mission (Part One)

Last month, the Defense Department published an updated version of their Homeland Defense manual (Joint Publication 3-27). Admittedly, I’ve never read this manual before and just noticed that a new version was released. This manual’s been around for a while, however, the last major prior update occurred in 2013 and 2007 before that. Joint Publication 3-27 contains some real gems of information should the U.S. military be called in to quell unrest or respond to a domestic conflict. Here are some notes on the first chapter, Fundamentals of Homeland Defense. I’ll write up notes for other chapters (Parts II+) in the coming days.

[Homeland Defense] is the protection of US sovereignty, territory, domestic population, and critical infrastructure against external threats and aggression or other threats, as directed by the President of the US.

– Starting on Page I-5, the manual covers a host of potential threats to the homeland. They include chemical, biological, radiological, and nuclear (CBRN)/weapons of mass destruction (WMD), rogue nation threats, transnational criminal organizations (like MS-13), “ongoing illegal immigration and potential special interest aliens”, and “presence of homegrown violent extremists”.

We’re going to focus on the presence of homegrown violent extremists and a potential military response under a homeland defense (HD) mission.

Page I-6 gets interesting. Subsection (I)(3)(1) describes the Posse Comitatus Act (PCA), which prohibits the regular Army and Air Force from participating in civilian law enforcement activities within the homeland. There are two exceptions to this rule: the first is an act of Congress, and the second is described as a “Constitutional exception to the PCA”. This exception covers missions considered as Homeland Defense; in other words, the regular Army and Air Force are able to operate within the homeland if it’s a matter of national defense. (For more information, see What You Need to Know About Military Assistance to Civil Disturbances.) I’m not a national security lawyer, but that might be a matter for the president to decide. If a domestic conflict or civil war were to break out, then the regular Army, not just the National Guard, could be called out for a homeland defense mission.

Let’s take this one step further: subsection (I)(3)(2)(b) covers the “Acquisition of Open-Source Information”. Typically it’s illegal for the U.S. military to gather information about U.S. Persons, but is this still the case during a Homeland Defense mission? And which organizations would be responsible for collecting intelligence information on U.S. Persons during a domestic conflict/civil war? In other cases, that’s usually part of the mission for local, state, and federal law enforcement and the Department of Homeland Security. During a Homeland Defense mission, would Army Signals Intelligence be collecting against U.S. Persons? How would NSA be involved? Would Army intelligence analysts be building organization charts and targeting packets for U.S. citizens? These are questions worth considering, and I’ll circle back around to them in a future edition of the Forward Observer Daily.

Subsection (I)(3)(2)(d) covers the use of unmanned aircraft systems (UAS), which says the domestic use of military UAS outside of established “policy, law, or other guidance” would require SecDef approval. A Homeland Defense mission would almost certainly rely just as heavily on UAS (armed or unarmed) as the U.S. military did in Iraq and Afghanistan — which is to say, we’re talking about a lot of drones. ‘A lot of drones’ means a lot of analysts watching drone feeds and lot of activities and locations being tracked. A single, localized insurrection or rebellion is going to have a lot of attention, per capita, as opposed to widespread violence across the nation. I remember when NSA whistleblower Bill Binney warned that our country was inches away from a “turnkey dictatorship” and something like a domestic conflict could certainly tip the scales if that were politically palatable.

Subsection (I)(3)(2)(e) covers “Incident Awareness and Assessment” (IAA) and it appears that SecDef approval is all that’s needed for military intelligence support to a Homeland Defense or Defense Support to Civil Authorities mission. “Traditional intelligence capabilities” for IAA could be used for:

  • situational awareness
  • damage assessment
  • evacuation monitoring
  • search and rescue
  • [Chemical, Biological, Radiological, and Nuclear] assessment
  • hydrographic survey, and
  • dynamic ground coordination

I’ll have to bang out another article on these tasks and topics at a later date.

Subsection (I)(3)(3) covers Military Information Support Operations (MISO) — things like psychological operations, information warfare, etc. — which could be used in what’s called Civil Authority Information Support (CAIS) “during domestic emergencies within the boundaries of the US homeland”. Activities would include the dissemination of information relating to national security or disaster relief and, according to this manual, do not appear to include information operations targeting the U.S. populace, although I’ll have to refer to some experts about this.

Subsection (I)(3)(4)(a) covers Rules of Engagement (ROE). “US forces, when performing an HD mission, must be prepared to engage the enemy [in accordance with] the appropriate [rules of engagement] and [rules for the use of force].” The ROE would be issued by military authorities, and presumably those authorities and/or the SecDef would govern changes to the standing ROE. The rest of this subsection covers the legal aspects of ROE, however, it does include the following statement: “Self-defense is an inherent right and obligation exercised by the unit commander in response to a hostile act or demonstrated hostile intent.”

Section (I)(5) covers the Homeland Defense Operational Framework, and I do have some general questions. This section specifically mentions the requirement to defend against threats to critical infrastructure, key resources, and the domestic population. The language sounds as if its referring explicitly to foreign threats — i.e., invasions — but a domestic conflict is likely to include internal threats to critical infrastructure and key resources. Consider that the National Guard is standing up cyber units and some of them are actively training to secure the grid and other infrastructure. I would expect the cyber space to be contested during a domestic conflict. “Hacktivist” groups have taken aim at targets in the past, and I expect them to in a domestic conflict, as well. This is probably not considered very often when we talk about domestic conflict, but there is certainly the risk of some major systems disruption if fringe groups consider targeting critical infrastructure and key resources. Hacking critical infrastructure, for instance, in “red states” could become a common occurrence during a domestic conflict. Even foreign exploitation, such as causing systems disruption to cities, could cause significant loss of life, disrupt public services and utilities, and generally make life more difficult for inhabitants. We should take this threat seriously and not overlook the possibility of foreign interference in a domestic conflict. This topic probably deserves an entire series dedicated to looking at the possibilities.

On that note, subsection (I)(5)(c)(2) points out that “land operations” and the “protection of critical infrastructure” are included in the HD mission. Critical Infrastructure is one of our six layers of the Operating Environment (ref: the Area Intelligence Course), and this subsection just underscores the importance of knowing what’s in your area.

Another consideration is subsection (I)(5)(f) which states that deterrence is a major part of the HD mission. My first thought is, If a domestic conflict were looking likely — an increase in civil unrest, political violence, violent rhetoric, etc. that encourages widespread violence — what might the National Guard or military do in response? If this were a situation where law enforcement was not an adequate deterrent, might we see mobilizations and staging activities by the military as a “show of presence” or “show of force” to deter more violence? Might there be an information operations effort by government or law enforcement to deter groups organizing for political violence? Developments like these might be a good gauge or provide early warning if federal law enforcement thought there was a moderate or high likelihood of domestic conflict. A change in tone or a series of public service announcements or some other information effort might be a good indicator that the risk is considered to be significant or imminent. This could take the form of publicized arrests and trials, a broader effort by law enforcement to identify known or suspected “radicals”, radio and television ads, etc.

I’ll finish reading up on the next several chapters this evening and I’ll prepare some more notes, especially for Chapter III and the Appendices.

If you’re interested in the potential for these scenarios, or concerned about where we could be headed as a country, then stay up to date with developing conditions with our threat intelligence reports. Each Friday we publish two intelligence summaries:

  • Alt-Observer, a weekly look at the development of domestic conflict, revolutionary political movements, tribal violence, and other factors that disrupt our “civil” society.
  • National Intelligence Bulletin, which covers issues of national security, domestic systems disruption, risk of failing critical infrastructure, and threats to social, political, and economic stability.


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Always Out Front,

Samuel Culper


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Samuel Culper is a former military intelligence NCO and contract Intelligence analyst. He spent three years in Iraq and Afghanistan and is now the intelligence and warfare researcher at Forward Observer.

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