Defense – Obstacles Part I: Introduction

So far we have covered fields of fire and observation, cover and concealment, and now it’s time to tackle obstacles.  Note I’m going to venture a bit away from normal military doctrine in covering obstacles.  What is an obstacle?  An obstacle is either a natural, man improved, or man made feature that is designed and placed in such a way that it will frustrate, channel, delay, or otherwise impede a threats movement (the obstacles goals).  Notice there’s no stop but just delay.  That brings us to a few basic truths about obstacles.

  • Obstacles will not stop a threat.  They will delay it, but a determined threat is going to eventually breach an obstacle.
  • Obstacles that are covered by observation and fire are more effective at accomplishing their goals than unobserved ones.
  • Obstacles that are concealed typically frustrate the threat better than visible ones.
  • Placed correctly an obstacle can channel the threat into your field of fire.
  • Natural obstacles tend to be the most effective.  Man made the least.
  • It is much easier to halt or delay a vehicle than a person on foot with an obstacle.
  • Obstacles require periodic checking and maintenance to remain effective.
  • And finally the greatest truth of them all:  Any obstacle that’s going to delay a threat getting in is most likely going to delay YOU getting out.

Keep those concepts in mind when you develop an obstacle plan.  An obstacle plan simply defined is the concept of what obstacles go where for what reason and how they work together in conjunction with the rest of your defense plan.  Your obstacle plan should exist at two levels.  The first level is for your homestead and your land.  The second level is at the tribal level.  During the next few entries I’m going to go into the different types of obstacles we’ll typically employ and then to close it out by applying  them to our case study.

Above I stated the first type of obstacle for our purpose is natural.  A natural obstacle is any natural feature found already existing in the environment that will accomplish our goals.  Natural obstacles include bodies of water, terrain features (such as cliffs, steep draws and jagged spurs, and depressions), thickly forested areas, and any kind of terrain that makes crossing it a slow-go/no-go effort.   Natural obstacles can also include certain types of vegetation.  Cactus fields, blackberry patches, and thorny thickets are all types of natural vegetation obstacles.  It is always sound practice to exploit any natural obstacle when given the opportunity.  For example rather than positioning an observation post in terrain where there’s no real natural impediments around it maybe putting it near a cliff edge would be wiser in that it would be better protected from a frontal assault.  For a general rule of thumb if you are going to remove a natural obstacle then it’s smart to consider replacing it with something else such as a man-improved obstacle.

Now the phrase “man improved” is a bit misleading.  The word improved doesn’t mean make better here.  Instead it implies that a natural feature has been changed somehow by human effort.  As an example – in our case study so far we clear cut a pretty dense piece of wood line to increase our fields of observation and fire however we also removed a natural barrier to vehicle movement.  But by leaving our 4 inch stumps instead of completely removing an obstacle we have modified it.  It might not be as effective as those woods would have been at delaying a vehicle but it will still accomplish that task. That’s another illustration of tradeoffs that you are going to frequently encounter when dealing with obstacles and the rest of your defense plan.  In that instance we needed clear fields of observation and fire to improve standoff (which was a higher priority) so the trade off was worthwhile.  Another goal of a man improved obstacle is to maximize the effectiveness of existing terrain that may not be a normal obstacle.

Man made obstacles are what most folks typically think of when they hear the word obstacle.  Wire is probably the most frequently used and the first to come to mind.  However barriers, ditches, varying materials, and other features that are placed by humans are considered man made.  Man made obstacles are normally the most resource consuming of the three types however if planned and executed properly can produce excellent results.  Traditionally man made obstacles are most effective when used in conjunction with both natural and man improved obstacles.

Ensure you weigh all of the impacts of what an obstacle will do including the possible necessity of moving out of the area and any requirement to access features outside of that area when developing your obstacle plan.  It would seriously suck to cut the only bridge leading out of your area and then need to get out of dodge in a hurry across that area if you were being assaulted.  When making those considerations think about alternative routes or possibly even creating a new route that affords a little more defensibility.  It’s also smart to take into account your estimate of the threats capability.  If you know the threat is moving around pretty much just in pickups then you wouldn’t necessarily require an obstacle designed to stop a tank would ya?  Using your Situational Awareness and Threat Estimate when planning obstacles will help you get the best bang for your buck and stretch your resources farther.

So who do we let know what is where when it comes to obstacles?  Here’s where OPSEC comes into play.  If I emplace some serious wire obstacles on my land and conceal them I’m probably going to let my neighbors on either side know where they are with the understanding that info goes no further than them.   Why?  Those neighbors may have to rally and help push back an assault on my homestead.  Likewise I’m going to ask my neighbor if he’s got any surprises  in case I have to do the same.  If your tribe forms a Rural Defense Force (RDF) that is going to react to attacks it’s probably a good idea for them to know as well.  This is where tribal trust comes into play.  Swear it by oath, blood, whatever but make damn sure everyone understands the confidentiality of it.  OPSEC uber alles amigos.

Now when you go emplacing obstacles on your own land that’s one thing but when you start putting them in areas and along features where it could impact the Tribes functioning then you might start running into problems.  IMHO any obstacle that is going to impact a roadway, bridge, or common feature (i.e. the church in our case study) really needs to be discussed amongst the tribe.  Let folks play the devil’s advocate and look at alternatives as I mentioned above.  Use your tribal decision making process to determine what kind and if they go in or not.  If folks go against it be ready to plead its viability and likewise be ready to make an argument against obstacles that would be frivolous.

So I want to send some folks out to lay in some obstacles.  At this point if it’s pre-SHTF then probably the only ones you are going to emplace are going to be on your own land.  But once things get hairy your tribe may decide to go out and emplace some in common areas.  To do this it’s best to utilize an Obstacle Party.  An Obstacle Party is a group of armed folks divided into two elements – the work detail and the security detail.  The work detail are the guys (or gals)  actually doing the work.  The security detail are the guys (or gals)  on watch and defending the work party during an initial contact with a threat.  An obstacle party should have a leader (either designated or elected however you choose to do it) to provide monitoring of work and make sure things go smoothly while keeping an eye on the defenses.  He (or she) is the whipcracker for this crew.  Make no mistake once contact is made work on an obstacle probably needs to stop and everyone fight but having that initial security detail to either alert or return fire can help buy you some time.   To minimize fatigue in the work detail and complacency among the security detail it’s usually prudent to rotate folks back and forth between the two.  But anyone not working on emplacing the obstacle should be providing security. The goal of the Obstacle Party is to emplace the obstacle as efficiently as possible while retaining a defensive capability.  Later on when we get into the Rural Defense Force issues we’ll cover things like planning, organizing, and executing Tribal patrols and work details.

Up next we’re going to look at some natural obstacles and ways we can exploit them.  Here’s some further reading for those so inclined:

Air Force Handbook 10-222 Civil Engineer Guide to Fighting Positions, Shelters, Obstacles, and Revetments

Army Field Manual 7-8 The Infantry Platoon and Squad Ch. 2 Section X Obstacles

Army Field Manual 5-102 Countermobility

About Treaded

Semi-retired career and contract troop. I own and maintain my own small ranch out here in beautiful rural America.
This entry was posted in Defensive Measures, Hardening the Homestead, Security Planning, Terrain and AO Development. Bookmark the permalink.

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