Monday, July 6, 2015

D-Day Lessons

ComNavOps is currently reading the book, D-Day June 6, 1944: The Climatic Batle of World War II, by Stephen Ambrose.  The book is quite extensive at over 600 pages and is more of an oral history than a pure academic study, however, there are strategic and tactical lessons packed in throughout the book if one reads between the lines and can do a bit of self-assembly of the events and lessons.

Here  are some tidbits from the book that offer lessons relevant to today’s amphibious assault concerns.

Discussing the concept of defense of the western European coast from the anticipated Allied amphibious invasion, Field Marshal von Rundstedt, Western European Commander, argued against dependence on fixed fortifications.

“He argued that the Germans should hold their armored units well back from the coast, out of range of Allied naval gunfire, capable of mounting a genuine counteroffensive.”

This was a potentially devastating strategy that the Germans failed to implement thanks in large measure to Hitler and Rommel's personal obsession with fortification defenses.  This strategy offers a warning to us, today.  A peer defender will, undoubtedly hold back reserves and we must be prepared to deal with them.  Simply winning a foothold on the beach (or inland location in the case of vertical assault) is not enough.  Just as there will be defense in depth, so too must there be the ability to apply offense in depth. We must be prepared to attack not only the immediate assault site but the defender’s depth as well.

Not only will defenders withhold troops and armor from the immediate assault point but the existence, today, of long range rockets and missiles adds an additional element of defense in depth.  Given the extreme range of today’s missiles, we must be prepared to extend the assault for hundreds of miles – no easy task.

The importance of combat engineers is emphasized.

“Almost one-quarter of the American troops going in on the morning of D-Day would be engineers.  Their tasks, more less in this order, were to: demolish beach obstacles, blow up mines on the beach, erect signs to guide incoming landing craft through cleared channels, set up panels to bring in the troops and equipment (the color of the panel told the ships offshore which supplies to send in), clear access roads from the beach, blow gaps in the antitank wall, establish supply dumps, and act as beachmasters (traffic cops).”

Contrast this to today’s lack of emphasis on engineering tasks and the lack of specialized equipment for the engineering tasks.  Among other needs, the US desperately needs a modern, specialized Combat Engineering Vehicle (CEV).

The debilitating effects of sea-sickness are pointed out.

“Bingham [Maj. Sidney Bingham, CO, 2nd Battalion, 116th] did an analysis of what went wrong for the first and second waves.  Among other factors, he said, the men were in the Higgins boats far too long.  ‘Seasickness occasioned by the three or four hours in LCVPs played havoc with an idealism that may have been present.  It markedly decreased the combat effectiveness of the command.”

Consider that time frame of 3-4 hours rendering troops significantly less combat effective and then consider the Navy/Marine’s desire to move the assault starting point out to 25-50 miles with the resultant possible increase in transit times.  Yes, an LCAC can travel at high speeds but LCACs are not doctrinally considered as initial assault transports.  At the moment, we only have AAVs.  Various ideas have been put forth for dealing with the extended transit but none have yet been adopted.  Transport to the beach is a serious shortcoming today.

Mobility, on both sides, is discussed.

“Once in France, the Allied paratroops and seaborne troops would be relatively immobile.  Until the beachhead had been expanded to allow self-propelled artillery and trucks to come ashore, movement would be by legs rather than half-tracks or tires.  The Germans, meanwhile, could move to the sound of the guns by road and rail – and by spring 1944 they would have fifty infantry and eleven armored divisions in France.”

This is a potentially profound lesson for today’s proponents of aviation vertical assaults.  Once on the ground, the troops have little mobility and become, in essence, a fixed target.  The enemy can move large amounts of troops (and armor!) to the attack point fairly quickly.  An aviation assault, with its utter lack of armored vehicles must succeed in its mission quickly or risk being overwhelmed by responding enemy troops.  Further, additional support to interdict enemy troop movements by road or rail is mandatory, requiring that the aviation assault be much larger in scope than the mere assault element, itself.  How to provide that additional support at a, presumably, far inland location is a question not answered by current doctrine.

It was recognized that the initial assault was not the only or even the biggest challenge.  Sustainment of the assault was vital and problematic.

“So the Allies really had two problems – getting ashore, and winning the battle of the buildup.”

As we’ve discussed, sustainment of an assault is the real challenge and is a real shortcoming for US amphibious forces today.  We lack the numbers and types of transports and connectors to sustain a major amphibious assault.

The logistics of moving troops from ship to shore was the major impediment to the assault.

“… the chief limiting factor in planning the invasion was lack of sufficient landing ships and craft.  Indeed, that was the single most important factor in shaping the whole strategy of the war, in the Pacific, in the Mediterranean, in the Atlantic.  Churchill complained with some bitterness that ‘the destinies of two great empires … seemed to be tied up in some goddamned things called LSTs.’”

In a similar vein, General Eisenhower is quoted in the book as crediting the Higgins boat with winning the war.

“If Higgins (the inventor) had not designed and built those LCVPs, we never could have landed over an open beach.  The whole strategy of the war would have been different.”

The US has allowed its fleet of LSTs and other such vessels to nearly vanish.  We lack the means to get a sufficient number of troops and, more importantly, armor and artillery ashore in a useful time frame to say nothing of the follow on (sustainment) munitions, food, fuel, etc.

We see, then, that the historical example of D-Day offers many lessons that are still relevant today.  Yes, technology may have altered a few of the lessons but the alterations are more a matter of degree than obsolescence. 

I’ll offer a few more posts of this nature based on this book.  D-Day and its lessons are too important to leave in the dustbin of history.


  1. Two posts on the subject of combat engineering and logistics for you


    1. Very nice articles, as always. Thanks for the links! Even today, the U.S. remains reluctant to invest in specialized engineering vehicles. Puzzling.

    2. The British and Canadians, by design, faced the toughest objectives and the strongest German army formations or the Normandy operation. I am an American, but credit must be given to our allies where it was well earned.

      Also, I highly recommend the book: Hobart's 79th Armoured Division at War: Invention, Innovation and Inspiration.

      Marines Under Armor provides a good counterpoint to over-zealous emphasis on infantry operations: armor was very much in demand in the PTO. Tarawa was a real wake up call for the Corps and the nation.

      The U.S. Army and Marine Corps were very much impressed by the UK engineering vehicles, but the atomic era, reduced military spending (for ground forces anyway) and the loss of corporate memory are responsible for the current state of affairs.


  2. I agree with all of your points except one. German Armor could not move during the day due to Allied airpower and supremacy. Indeed few armored divisions ever made it over to face the Americans and the one that did Panzer Lehr was obliterated in the carpet bombing that opened the way to St Lo and Avaranches.

    Not that I think that Airpower rules, but these are great examples of where CAS completely negated the enemy his choice tactic, maneuver and concentrate for strikes. He was forced into a grind it out defensive battle that he ultimately lost.

    NOTE that CAS did this NOT strategic bombing. KEEP THE A-10!

    1. This is actually an example of air interdiction, not CAS. It was done primarily by non-CAS-specialized aircraft.

    2. We did employ heavy bombers at Normandy but they caused mass destruction to towns and Germans and allied units. After killing General McNair and a few hundred other Americans due to yet another "error" Ike banned them. They went back to slaughtering German civilians.

    3. A minor point of order. When you are bombing the enemies front line units, you are doing CAS. Interdiction was blowing the bridges over the rivers further back.

      Yes interdiction stopped units from moving, but destroying them (Panzer Lehr Commanders report) on the front line is CAS.

    4. I would agree that the role of CAS has been underrated during D-Day.

      The P-47s under Lieutenant General Elwood Richard Quesada played a very important and underrated role.

      I think that many of Patton's advances might not have been possible later on without them.

    5. The main value of air power at D-Day was preventing movement of German reserves forward to counter attack the landing. Fighter bombers hit railways and attacked wheeled vehicles in the enemy's rear areas. This is interdiction, not CAS.

    6. Smitty: your points are well taken, but the real story is that Allies were able to adapt the vast numbers of fighters that were used to smash the Luftwaffe, into a hugely effective ground attack force.

      The question for the military in the 21st century is if we can/should still expect aircraft to perform this role.


    7. "The question for the military in the 21st century is if we can/should still expect aircraft to perform this role."

      One difference between then and now is that the aircraft of WWII were quite cheap even by the standards of that time. Thus, the willingness to hazard front line fighters as low level attack aircraft was much greater than we would have, today, with a $150M aircraft. A Raptor, for example, might well make a good low level strike aircraft but are we willing to risk losing it? We don't have thousands of extra Raptors as the we did with WWII P-47s, P-51s, and whatever else was pressed into service as low level strikers.

      I suspect that we'll find we're risk averse to using the F-35, for instance, even in its intended role because we'll have so few of them. The issue of monetary-induced risk aversion is one I've brought up in numerous posts and I think it is and will be a significant phenomenon.

    8. @Smitty,

      There many more hard questions that need to be asked, particularly given the general confusion between *ground support*, *CAS*, and *interdiction.*

      1. Artillery vs CAS/Interdiction. The ready availability of CAS has been used to justify sharp reductions in artillery support – a questionable outcome, particularly at the tactical level. Ground commanders should have sufficient fire support to conduct tactical operations: TACAIR should be allotted to achieve operational and strategic objectives. Once air supremacy is established it frees up air frames for ground attack: given the absolute air supremacy we have enjoyed from ~1943 on, we have been able to support even isolated squads in OIF/OEF; but this may not work out so well against a peer competitor in the future.

      2. Training/coordination. Fighter squadrons are not currently funded to properly support training for the air-to-air and air-to-ground missions – logically, the ground support mission should be shorted in favor of air-to-air. Ground support, particularly CAS, requires intensive specialized training and ideally collocation of the air and ground forces: post 1991 operations against weak competitors lacking airpower and having minimal AAA capability, combined with nearly static friendly force dispositions have allowed us to ignore this. It is unclear if the USA and our allies will be able to operate in an environment where our sensors, communications, and intelligence are challenged or degraded. You cannot park aircraft in orbit at 30,000+ feet in an environment with sophisticated air defenses. You cannot coordinate air and ground forces in a contested environment when the commanders are unable to consider the situation jointly. There is also an OPSEC dimension to this.

      3. Suitability of aircraft. Just as the navy found the guns of its ships to be well suited to supporting amphibious landings, the mid-war fighters of WWII were generally well suited to the interdiction mission. The aircraft had excellent slow speed/low altitude maneuverability, were robust, could be sortied multiple times a day, could operate from airfields close to the action, carried suitable armament to the task, and were cheap enough to repair or replace. Tactical jets have generally proven to have trouble visually identifying targets, and have marginal low altitude low speed flight characteristics. Again, we have been lucky that the Taliban/ISIL/AQI lacked credible air defenses and the campaigns have largely been fought in deserts. The NATO air campaign in Serbia should raise some serious doubts about everything from our aircraft capabilities to our ROE.


    9. GAB, as always, absolutely fantastic comment! I particularly like the point about parking aircraft at 30K ft. Someone should ask you to write a guest post!

    10. GAB,

      I don't get how you can say we can't fly sorties at 30k+ ft against a sophisticated air defense in one paragraph and then advocate for "low and slow" aircraft in the next. The "low and slow" environment has been lethal to aircraft since before Vietnam, and would be exponentially more so against a sophisticated air defense. Google Tunguska, Tor, Igla, Verba, QW-2, Type 95, and even Shilka VSHORADS.

      The only aircraft that should fly low and slow are those that we don't mind losing (I.e. UAVs).

      We have well established doctrine for dealing with high altitude threats, but no effective doctrine for dealing with the low altitude threats other than avoiding them.

    11. Smithy, what he said was that we can't stack aircraft in a high altitude holding pattern for indefinite periods waiting for a call, as we currently do. His point, I think, is that the procedures we've developed for CAS against low end opponents won't work against a peer.

    12. we already have doctrine to deal with this too. Stacking aircraft in holding patterns is just a matter of convenience, nothing more. In fact we don't typically keep that many aircraft waiting in holding patterns if there are other targets available. That's wasteful.

      Instead we use "Push CAS" to limit pointless boring holes in the sky.

  3. Only generally related to this post, Snafu posted some interested pics of the Chinese MLP equivalent. Its just big enough to carry a Zubr-class LCAC on deck. This gives the Zubr the strategic mobility it lacked, combined with its speed and cargo capacity. Definitely worth checking out.

    Randall Rapp

    1. Randall, SNAFU is on my daily reading list but I appreciate the heads up! Now, do you think the Zubr is a good idea, generally? Only effective against a non-peer? Just a big fat, high risk target against a peer? An effective means of landing armor in the initial wave? Something else? What's your take on it?

  4. Ambrose is more a flag waver than a military historian, which is why he is popular. Rommel experienced allied airpower in Africa and knew any large counterattack force would be smashed on the road. Hence fortifications, which deterred the allies from Calais and other ports. He had smaller division size armored units for counterattacks, but those were withheld too long because Hitler was certain Normandy was a diversion. The lesson remains. LSTs are the ultimate amphib vehicle, and we have no more.

  5. An excellent video talking about the myths surrounding US armor in WW2, along with a couple of other items like CAS, is here:

  6. I would have to disagree about the fact that Rommel would have advocated for fixed fortifications - he was always an advocate for mobile armor, although he had become as a result of his experiences in North Africa increasingly pessimistic due to Allied air power.

    D-Day actually very nearly failed. Many of the tanks, artillery, and heavy equipment either did not make it or badly fumbled their landings.

    They had the good fortune of surprise - the Germans were astonished at the time they landed. That and in the case of Rommel, he had apparently left to celebrate his wife's birthday.

    One thing I will note that you probably should also discuss is the role of naval gunfire support. Perhaps ships like the battleship will never fight for supremacy of the seas any more, but they proved invaluable in shore bombardment.

    Basically the conclusion I have is - amphibious landings are very difficult because you need:

    1. An area low in naval/land mines
    2. Total surprise (attack lightly defended positions)
    3. Naval superiority and heavy support fire
    4. Total air superiority
    5. A lot of engineers and logistics

    That's a tall order.

    1. Alt, with respect, there is nothing to disagree about concerning Rommel. It's documented that he advocated for fixed beach defenses. Historians and strategists agree that this seemed incongruous from him and, yet, that's what he wanted.

      The role of D-Day naval gun fire is addressed in one of the next couple posts! I have more lessons of D-Day coming.


Comments will be moderated for posts older than 7 days in order to reduce spam.