Note: This is part of a series. Read parts one and two here. The corners are our main areas to clear in a “traditional” entry, as discussed in the previous article. This part of the series will look into the tactical significance of the room anatomy in relation to human inhabitants, as well as a few more minor structural concepts that are not “concrete anatomy.” To start off, we will further discuss corners. Are your ears bleeding yet? Get used to it.

Corners are the areas we clear in our primary sweep. We know that. So what? Well, corners in relation to human beings are areas people tend to “hug” in certain circumstances. If they are in immediate danger, under fire in a firefight, feel they cannot defend the room effectively, or feel they will gain surprise by being in a corner, they will “hug” it. It makes them feel safer; they have solid walls to either side of them, and only one area to focus on ahead of them. Cozy. It’s bad news for us. We enter the room facing someone with a weapon trained on the point of entry—someone who may feel safe, even confident, in this position. A dickhead with an AK can kill a million-dollar super soldier from this position. You may recognize that I’m trying to emphasize the importance of clearing corners. Clear them effectively.

They may hug the corner with the biggest field of view of the entry point—the soft corner. They may use cover and barricade themselves in this way using deep angles within the room. They may want to stay out of sight, relying on surprise from the hard corner. From this position, they may not be barricaded. They may be sitting “exposed” in the corner with no cover. If you clear the soft corners from outside, then you can conduct a targeted approach to the hard corners. Now you see why understanding these differences in corners becomes significant. At least I hope you do.

You have a few more areas to think about, the first being the immediate threat area, then the corners, and then the rest of the room. This is known as a “center-corner-center” approach. We’ve already discussed corners, so let’s take it back a step.

The immediate threat area

The immediate threat area can be seen as an area close to the entrypoint where an enemy may engage the entry team or obstruct the entry. If an enemy is within this area or looks to obstruct your entry, they are known as an immediate threat. The definition of an immediate threat is:

  • A person armed and prepared to fire upon the entry team
  • If not eliminated or subdued, they will cause harm to the entry team or inhibit the entry process.

Other definitions further describe an immediate threat as:

  • A person who blocks movement of the entry team
  • Within an arm’s reach of the entrypoint.
Immediate threat area (estimated) and an immediate threat.

These are not imminent threats. An imminent threat is impending or likely danger that is separated by space or time. An immediate threat is actively happening in real time. It is a present danger that is next in order, without delay. For example, an imminent threat may be running across the room to grab his rifle, which is sitting meters away. This means you have a few vital seconds. Imminent. An immediate threat has the rifle in hand and is ready to operate it. A potential threat, furthering this point, is someone who may potentially become dangerous in the future, and is thus treated as a threat for a short duration until defined.

Now, an immediate threat area is not the “base anatomy” or “concrete anatomy” of the room. It is a tactical concept superimposed on the anatomy. The immediate threat area is a concept of how humans use the anatomy. This is equally important to know as the room’s anatomy. It has tactical significance. Eliminate immediate threats, if you can, as soon as possible. Even before reacting to the hard corners.

We understand that the immediate threat area and hard corners are our initial targets. Usually, the first two men entering will clear these areas first. But how do we do this without hurting one another? How do we use the anatomy to prevent risk, especially if we have to engage somebody in front of us?

To prevent any mishap with the third and fourth man entering after first and second, or the point man and second man progressing too far into the room, there is a key fundamental concept: the strong wall.

The strong wall

“Sticking to the strong wall,” or strong-walling, minimizes the risk of friendly fire (blue on blue) and allows for a coordinated entry into the room while maximizing the visible area in the room.

The strong wall, or the common wall, is the wall along the entry point. In a corner-fed room, this may include both walls connecting to the door, but under normal circumstances, it is one individual wall. Example: In some entries, you run along both known walls attached to the original entry point wall. If this is done correctly, there should be safe firing lanes. You may have seen some of the “Special Forces room-clearing videos on YouTube. One of them displays this perfectly. You see comments on it saying, “Wow, I’m like sooo amazed they like didn’t, like, shoot each other.” Well, that’s why. Pretty simple concept, huh?2

Strong-walling is a dynamic process, which is why I have not included it as a part of the concrete anatomy, but it’s still an area of the anatomy we mentally visualize and use to our advantage. The strong wall/s may be going to the left or right, and may be one wall or two. It all depends on what the room anatomy is telling us. The point is, you remain on the same wall as the entry point, locking down and engaging threats within that room without leaving the wall.

Basic threat assessment and movement

  • Immediate threat area: An area that can be close to the entry point, but definitely has access in which to visualize and engage the entry point.
  • Immediate threat: A person prepared to cause immediate harm to the entry team, usually within seconds, or as the entry team enters the room.
  • Imminent threat: A person not yet capable of causing immediate harm, but actively seeking the capability to do so. For example, moving toward a weapon or crossing from the other side of the room toward the entry team.
  • Potential threat: A person who may have the capacity to cause harm—they are potentially dangerous. This is why all hostages get the zippy and a hostage controller looking over them, folks.
  • Strong wall: The wall running along the entry point. “Strong-walling” is a tactic in which all members of the entry team stay along the strong wall to lock down and engage threats.

The next article will cover some of the additional obstacles we may face that encompass the anatomy of the room. These obstacles might catch you by surprise.

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