Thursday, August 1, 2019

Amphibious Assault - Port Seizure

I’ve previously discussed amphibious assaults and stated that I consider the need for such assaults to be extremely unlikely under any foreseeable strategy.  Sure, there could be the odd small scale raid or diversionary feint but there just is no need for large scale assaults. 

However, the Marine Corps insists that such a capability is needed so let’s address what I consider the most likely amphibious assault scenario: a port seizure.  The Marines refuse to discuss it or even consider the possibility so we’ll do it for them. 

Short of a massive, multi-year buildup there is just no possibility of logistically sustaining a sizable invasion across a beach.  That only leaves the option of seizing an existing port to support the unloading of cargo ships at a rate sufficient to sustain a major invasion.  The astute historian will note that this is exactly what the objective of the WWII Normandy D-Day assault was.  Since all ports are associated with city structures and infrastructures, the roads leading to and from the port will prove every bit as critically important for quickly dispersing the unloaded supplies as the port itself.

Here are the main aspects of an amphibious port seizure and the more detailed points associated with them.

Initial Seizure

Port – The port, itself, must be seized, obviously.  The key is to seize it as quickly as possible, to minimize the time the defenders have to destroy the facilities such as cranes, piers, docks, ramps, and warehouses.  The best method of seizure is an initial airborne assault to quickly place infantry in and around the port to seize the facilities.  Simultaneous with the airborne assault must be an amphibious assault with heavier weapons, artillery, and armor to relieve the airborne troops and secure and defend the port.

Roads – Airborne troops should also be used to seize key roads leading in and out of the port so as to prevent immediate counterattack.  As with the port, additional amphibious troops will be required to relieve the airborne troops and secure and defend the roads.

Warships – It will be necessary to operate warships in the closed and congested waters of the harbor/port to provide cruise and ballistic missile defense, gun support, and counterbattery fire.  This is completely contrary to current Navy doctrine and will require new doctrine and tactics.

Mine clearance – It is hard to imagine that any modern port will not be heavily defended with mines.  Given that speed is the key to successful assaults, in general, and seizure of an, at least, semi-functioning port, mine clearance must be accomplished extremely rapidly to allow warships, supply ships, transports, and repair vessels access to the port.  For example, the WWII D-Day assault involved hundreds of minesweepers to achieve the necessary clearance in a combat-useful time frame.  Currently, we utterly lack the capability to perform this chore.


C-RAM (Counter-Rocket, Artillery, and Mortar) – Being a known, fixed location, a seized port will be subject to intense mortar and artillery fire.  Mobility, the mantra of modern militaries and the presumed solution to mortar and artillery fire, does not apply to seizing and holding a port.  Our forces will be static and fixed.  Uh, oh!  That’s an operational and doctrinal oversight!  C-RAM protection will be required. 

Missile Defense – Aegis warships will be required to establish a protective missile defense umbrella over the port.  This may be complicated by large buildings obscuring the radar view of the ships and may require an offboard, networked sensor.  However, we currently lack a communications and network system that is proven capable of functioning in the face of electronic and cyber countermeasures.

Road Defense – Roads are simultaneously the avenue for enemy counterattacks and the means of moving supplies out to the main invasion effort.  Defending the road system, especially early on, will be manpower (infantry) intensive and require large quantities of armor for mobile defense.

Repairs and Rebuilding

Barring some incredibly good luck, the enemy will likely destroy the port facilities to a very large degree.  We will need to rebuild most of the facilities.  We will need the ability to unload with only minimal port support while repairs are on-going.  We will need to rebuild under fire.  Who will do this?  How will they be protected?  What equipment is needed?  Are we trained to rebuild port facilities while under fire (hint:  we aren’t)?

Loading/Unloading Operations Under Fire

Since the port’s cranes will have likely been destroyed, we’ll need ships with their own large cranes as a stopgap unloading measure until we can rebuild facilities.  A dedicated crane ship or two would also come in very handy.  We’ll also need large numbers of fork lifts, trucks, etc. for quickly moving the unloaded supplies out and to the invasion force.  Initially, all of this will occur while under fire.  Are we prepared and trained to unload and disperse supplies while under fire?  Are we prepared to disperse supplies very quickly so as to avoid the buildup of large stockpiles (meaning very attractive targets)?


The key, and the entire point, to seizing and using a port is the ability to quickly disperse incoming, unloaded supplies out to the main invasion force.  The dispersal (meaning transport of supplies) will be complicated by the fact that there will only be one or two routes and those routes will be known to the enemy and, thus, subject to continual attack.  Are we prepared to fight our supply convoys through?  Do we have the necessary doctrine to secure roads, establish defended zones around the roads, and protect convoys?  Are we mentally prepared to inflict the degree of collateral damage on the surrounding areas that will be required to clear them of enemy forces?  Ironically, improvised explosive devices (IEDs) and mines, the bane of our Iraq/Afg efforts, will be a non-threat in this scenario since, presumably, we’ll kill anyone/anything even remotely approaching the transport roads – unless, you know, we try to fight a zero-casualty, zero-collateral damage type of war which would be incredibly stupid but is exactly what we’ve done in Iraq/Afg.


Other than for occasional small scale raids, over the beach assaults are neither feasible nor operationally warranted.  Port seizure, however, is mandatory.  There is simply no other way to logistically supply a modern, major assault force with the required volume and tonnage of supplies.  I believe that this is, or should be, the Marine’s core mission. 

It is obvious from the preceding discussion that port seizure requires a specific and specialized force with specialized equipment, doctrine, and tactics – almost none of which exists, today.  Being amphibious, the Marines are ideally situated to provide much of this capability although it would require a complete rethinking of their purpose and a complete rebuilding of their force structure. 

The issue of airborne troops, alone, is an interesting one.  Would these troops come from the Marines or from existing Army units?  Would the preferred airborne delivery be parachuting or helo insertion?  These are the kinds of questions that need to be explored in realistic exercises.  Unfortunately, to the best of my knowledge, there has never been a port seizure exercise by the US military in recent decades.

If port seizure is as important as I believe it to be then we need to begin developing the force necessary to do it.  If one would argue that port seizure is not important then I need to hear how we’ll logistically support a major invasion force.


  1. "Ironically, improvised explosive devices (IEDs) and mines, the bane of our Iraq/Afg efforts, will be a non-threat in this scenario since, presumably, we’ll kill anyone/anything even remotely approaching the transport roads"

    Not entirely true - artillery-scattered mines have been a thing since the 80s. Going by your assumption that the enemy force is going put up intense mortar and artillery fire, it isn't much of a leap to assume that at least some of their guns are going to be firing artillery-scattered mines. They don't need to approach the transport roads, not when they can fire from 2 dozen miles away and that's a low end estimate). By scattering anti-personnel and antitank mines at the port exits, even if no kills are made, it's going to delay the movement of forces out of the port, because you need to clear the mines, you need to clear disabled vehicles, and while you're doing that you're also eating regular HE and DPICM from the rest of your enemy's guns. And then even if you cleared the mines, well, these are artillery-scattered mines - they can just do another fire mission and reseed the minefield. But well, that's war - the other guy gets a vote. (which is pretty much Cold War US Army artillery thinking for how FASCAM would be used: seed minefields at bridges and other chokepoints to bog down advancing Soviet armor and make them easier targets for HE - and you don't need special guns to fire artillery mines, it's just a different shell. Fire FASCAM, load HE for the next fire mission.)

    The obvious counters would be bringing in mineclearing assets in the follow-on landing waves and tasking gunships and tactical air from the CVN and LHD to go artillery hunting, but that's got it's own problems and difficulties and isn't a sure thing, but I'm pretty sure we've discussed this before.

    "Would these troops come from the Marines or from existing Army units? Would the preferred airborne delivery be parachuting or helo insertion?"

    If the Army is involved, it's going to lean more to helo insertion. The problem with parachuting troops is that you have to find a large sized landing zone, and your paratroopers are so weighed down with gear that you are guaranteed to suffer injuries amongst your force, just from the landing. Big Army would rather do a heliborne assault from helos.

    Incidentally, it's worth keeping an eye on the progress of the Army's Future Vertical Lift program. AAt present, FVL is just for a VTOL utility squad transport, but the Army has its eyes on a much larger design for the the future, which would be in the same weight class as the C-130. Theoretically, if it comes to fruition, you'd have a theater-range VTOL transport capable of carrying a company of troops, or a squad of troops and an IFV.

    But given the Army's procurement debacles, that's a big if. (And it would also make Congress question why do you need a fleet of amphibs to do unsurvivable amphibious landings on opposed beaches, when the Army has these long-range VTOL transports...)

    1. "Big Army would rather do a heliborne assault from helos."

      To expand upon this a bit more - if a heliborne assault could be executed, Big Army would rather do that.

      An airborne assault might well be executed if that was the only way to surge troops to defend the port, with Big Army not having any nearby bases from which to launch a heliborne assault with.

      Otoh it really boils down to the specific geography of the region where the fighting is happening. Fighting in SEA is different from fighting in the Fulda Gap is different from fighting in the Balkans.

    2. " artillery-scattered mines"

      An excellent reminder. However, such mines do not seem a major problem. The only location that matters in terms of the movement of supplies is on the road itself. Such mines would be readily visible and, presumably, readily removed.

      Further, the high angle firing generally used for delivering a scatterable minefield also enhances the exposure to counterbattery fire. So, assuming we can get proper counterbattery capability emplaced, we can minimize the severity of the problem.

      Still, scatterable mines are a threat that needs to be addressed.

    3. @WIld Goose - great post!

      Also, there are a number of rapid mine scattering systems for aircraft, and also ground vehicles that can quickly seed minefields.

      Western nations largely gave up on these, but the Chinese and Russians lay retain very effective mine field deployment systems.



    4. Regarding scatterable minefields, remember that in an urban setting, there may well be buildings along the road(s) of interest which may interfere with the delivery of the mines - an unintended benefit of urban warfare!

      Imagine a trying to seed mines onto a road leading out of New York City. The buildings would provide significant protection, I would think.

    5. There are two airborne systems to deploy mines. One is the M-136 Volcano mine system which can be mounted on Blackhawk helicopter. The second is the GATOR mine system which is used by the Air Force. Both systems use the same anti-tank and anti-personnel mines.

    6. "There are two airborne systems to deploy mines."

      Assuming we don't want to mine ourselves, enemy airborne mine deliver is a very much lesser threat since the life expectancy of a helo or aircraft directly over a closely held battlefield is very short. Artillery would seem the only viable delivery method and that has its drawbacks, as discussed in other comments.

    7. "Regarding scatterable minefields, remember that in an urban setting, there may well be buildings along the road(s) of interest which may interfere with the delivery of the mines - an unintended benefit of urban warfare!

      Imagine a trying to seed mines onto a road leading out of New York City. The buildings would provide significant protection, I would think."

      "Assuming we don't want to mine ourselves, enemy airborne mine deliver is a very much lesser threat since the life expectancy of a helo or aircraft directly over a closely held battlefield is very short. Artillery would seem the only viable delivery method and that has its drawbacks, as discussed in other comments."

      @ComNavOps: It really depends on the topography of the port and surrounding city. In the first scenario you suggest, that gives room for helicopters to use terrain masking from both the natural terrain and buildings to mask themselves from the escort DDGs, which would be the the primary air defense umbrella, and getting down in the weeds and flying through streets affords a certain level of protection from US fighter cover (I'm assuming that any port seizure would have to be a joint op between the Navy and Marine Corps). Otoh, a port that has somewhat less built up surroundings (I'm reminded of the Port of LA) would, as you say, be a riskier proposition for aircraft and helicopters.

      You've got a point with regard to artillery, but otoh if the opponent is a serious player, they'll have invested into their own stockpiles of rocket artillery. The drawback of rocket artillery is the much longer reload vs tube artillery; otoh, what rocket artillery loses in sustained fire, it gains in range and salvo density. They don't call MRLS the Grid Square Removal Device for nothing. The problem, as I see it, is that rocket artillery outranges the tube artillery the Marines bring with them - there's nothing to stop an opponent from using 155mm guns to seed minefields, then pulling his guns back and having his rockets service the port or hitting vehicles getting caught in the minefield.

      As I see it, the challenge is basically going to be seizing the port fast enough and breaking out fast enough before the enemy can bog you down and delay your breakout from the port (or, in the worst case, keep your forces pinned in the port, subjected to intense fire, because there's no way the Marines' towed guns are going to be winning artillery duels against SPGs or rocket artillery).

      And now I'm thinking that the breakout force is probably going to need to bring along road repair vehicles as well, to fix the inevitable damage to the roads from mines and clearing those mines with explosive charges.

  2. I'm going to go out on a limb and suggest that you can remove the "under fire" from "Loading/Unloading Operations". I'm going to guess that the US has outsourced these functions and has no ability to organize them in a foreign port in a short time period with organic elements.

    In other words, the US Navy (or Army for that matter) no longer has the knowledge or trained resources to set up port operations from the ground up. Maybe I'm wrong and just too cynical...

    1. After the Haiti earthquake the AF setup an expeditionary ATC to start an air bridge. At the same time the army setup port operations. They no how to do it when nobody shoots back. A bigger problem is we have a virtually nonexistent merchant marine. We have no shipping to bring to the port. Foreign shipping is not going to come and play.

    2. "A bigger problem is we have a virtually nonexistent merchant marine."

      From the Bureau of Transportation,

      In 1960 we had 2900 US-flagged merchant vessel of 1000 tons or greater. In 2019 we have 180.

      This is slightly misleading, in a sense. The US 'owns' a large fleet of merchant vessels but they're foreign flagged. Whether those are accessible to us in the event of war, I have no idea.

    3. "The US 'owns' a large fleet of merchant vessels but they're foreign flagged. Whether those are accessible to us in the event of war, I have no idea."

      That depends on the kind of war you're fighting. The basic reason for the outsourcing of so many functions from the military is the same as for doing it in the civilian economy: it increases corporate profits. There has been a general assumption for decades that a war for national survival would be nuclear, and any non-nuclear war isn't a matter of national survival.

      So the corporations have seen the wars in Afghanistan and Iraq as chances for profit, and have generally done well out of them. This is why I think a war with China is actually unlikely: it would be terrible for corporate profits.

      The US faces a choice between long-term decline due to failing in economic competition with China, or actions that will be against the short-term interests of its own corporations. Don't feel too bad about this: the British lost world power in just the same way.

    4. "At the same time the army setup port operations."

      I've been looking into this since you mentioned it and I can't find too much material. What I have found suggests that some barges were set up to help unload supplies in lieu of the damaged piers. It's unclear how significant that effort was in terms of tonnage of supplies handled.

      Here's one of the better writeups I've found: Haiti

      If you have links to better references, please share them.

      What I've seen suggests that the Haiti port efforts were only marginally, at best, similar to the type of port operations we're discussing here.

    5. The following books deal directly with the impact of ports and logistics on the planning and execution (or failure to execute) the Normandy landings and the battles for western Europe:

      Gators of Neptune: Naval Amphibious Planning for the Normandy Invasion, by Christopher Yung, 2013, ISBN-10: 1591149975, ISBN-13: 978-1591149972.

      The Great Mistake: The Battle for Antwerp and the Beveland Peninsula, September 1944, by Peter Beale , 2004, ISBN-10: 0750932864, ISBN-13: 978-0750932868.

      Think Defense has a series of related articles on military use of ports, amphibious operations etc. - they are professional and comprehensive; here are a few links:


  3. Need to add "isolating the battlefield" with airpower and long-range strike systems, blinding enemy C3ISR, and suppressing air defenses.

    1. Yes, those are certainly all part of the overall effort. You have to understand, though, that I can't write a book on each post although, admittedly, each post is fascinating enough to warrant one!

      One of the keys to the Normandy assault success was the ability to interdict the German reinforcement and counterattack movements. That would be a important part of any port seizure.

      Recognize that I'm constrained to a several paragraphs and that means that I have to prioritize what's included and a lot gets left out.

  4. Great post, this is really interesting.

    It's hard to envision this type of operation succeeding without the Marines having a substantial amount of heavy armor and without the support of 8" and 16" naval gunfire.

    1. Yep, you've identified a few of the major weaknesses. The first thing that has to happen, of course, is that the Marines need to accept and embrace the mission which, thus far, they've shown zero interest in. I don't know how the American military thinks we'll support forces in the field without ports to unload and we're not always going to have friendly ports around, like we did in Desert Storm.

  5. This scenario is somthing that should be run through war games!! It could identify all the weak or non-existent links and then drive at least design-level equipment procurement. WWII was a showcase for relatively quick thinking and improvisation, with everything from Higgins boats to barrage balloons to flail tanks. Even if we dont procure items en masse, it seems design and prototype work should be happening/done ahead of time, and suppliers identified. The artillery launched mines example had me wondering for instance... What do we have to deal with that threat rapidly right now?? Do we have dozer blades to hang on M-1s, or somthing similarly useful?? Maybe commercially available loaders with some small arms protection added?? These small and un-sexy tools could make or break a battle (war??).....

  6. Another important possible mission for the Marines which I don't believe you've addressed in this or other recent posts: Rapidly deploying a combat-ready expeditionary force onto the shores of an ally in response to a rapidly evolving threat.

    For example, in the event that the PRC decides to launch an amphibious invasion of Taiwan, we might want the capability to rapidly land troops on the opposite (eastern) side of the island to support Taiwan's defense. If no port capacity is available or ports are denied to us by the PLAN, then we might want the capability to send those troops in (unopposed) over the beach. You could imagine similar situations where we'd want to rapidly deploy troops with heavy equipment in South Korea or the Philippines, at the invitation and with the consent of the local government.

    1. You've just covered it! An unopposed landing? Not much to talk about. Maybe I'm missing something? Is there some particular aspect of it that you'd like to address?

    2. "If no port capacity is available or ports are denied to us by the PLAN, then we might want the capability to send those troops in (unopposed) over the beach."

      Have you done the math on the number of troops we could send across the beach, unopposed, even if we used every amphibious ship in the fleet? Run the math and then compare the result to the kinds of numbers that were routinely used for amphibious assaults in WWII. Let me know what you find and what you conclude about the usefulness of even an unopposed unloading of troops.

      Hint: the July post, "Assault Ratio", has data on WWII assault troop numbers.

    3. What does a MEU, MEB, or even a MEF really add to a scenario where China invades (or Japan, or S. Korea, or the Philippines, etc.)?

      MEU = reinforced infantry battalion ~600 trigger pullers
      MEB = reinforced infantry regiment ~1,800 trigger pullers
      MEF = reinforced infantry division ~5,000 trigger pullers

      The active component of the Republic of China Army is about 100,000 troops, organized in a modern brigade structure, heavy on armor, mechanized infantry, artillery, and engineers.

      The USMC are light infantry, organized in an antiquated regimental system, lacking in effective training in operating in or alongside combined arms formations, have improvised wheeled and tracked transportation for the infantry, and lack *relevant* artillery forces (towed artillery is dead meat in a high intensity war).

      Most USMC Commandants and general officers have never commanded a division, or a regiment fighting as a regiment. so actual knowledge of regimental and division operations is mostly theoretical in the USMC. And in fairness, the USA has also not really fought in brigade sized or larger formations since 2003, but the Army has better institutional resources (doctrine, organization, logistics, etc.).

      Keep in mind that the 18th Airborne Corps could probably deploy at least a division (also of infantry) before the USMC could move a MEB from CONUS.

      General Wayne Downing once remarked that “In a real fight, you will be happy for any help you can get…”, so I am sure that the Republic of China will accept any aide; but the PRC’s PLA, which also fields modern armored and mechanized forces, is unlikely to be impressed by a few USMC infantry regiments.


    4. MEF = reinforced infantry division ~9,000 trigger pullers



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