One more panzer group in Barbarossa, plans for a two-year campaign

[TheMarcksPlan]

1. The WW2 Heer was not systemically bad at logistics. It was far better than RKKA even if outclassed by USA.

Juts False. Badly badly Wrong. The Germans just did not include logistics as part of their planning process. It;s every bit as bad as it sounds.

29 mins in for the lack of logistics in planning. but the first 40 mins is German command.

https://www.youtube.com/watch?v=5ZMPhACNCmI&t=3404s

Just a heads up guys - if your argument is just "watch this 1.5hr Youtube video" I will not:

• 1. Watch your video.
• 2. Take you seriously.

If you have an argument, make it - with evidence etc.

[pugsville]

1. The WW2 Heer was not systemically bad at logistics. It was far better than RKKA even if outclassed by USA.

Juts False. Badly badly Wrong. The Germans just did not include logistics as part of their planning process. It;s every bit as bad as it sounds.

29 mins in for the lack of logistics in planning. but the first 40 mins is German command.

https://www.youtube.com/watch?v=5ZMPhACNCmI&t=3404s

Just a heads up guys - if your argument is just "watch this 1.5hr Youtube video" I will not:

• 1. Watch your video.
• 2. Take you seriously.

If you have an argument, make it - with evidence etc.

I do give a time s stamp I donlt expect you watch it all. But fine.

[pugsville]

1. The WW2 Heer was not systemically bad at logistics. It was far better than RKKA even if outclassed by USA.

Juts False. Badly badly Wrong. The Germans just did not include logistics as part of their planning process. It;s every bit as bad as it sounds.

29 mins in for the lack of logistics in planning. but the first 40 mins is German command.

https://www.youtube.com/watch?v=5ZMPhACNCmI&t=3404s

Just a heads up guys - if your argument is just "watch this 1.5hr Youtube video" I will not:

• 1. Watch your video.
• 2. Take you seriously.

If you have an argument, make it - with evidence etc.

Ok The Argument is the German Army was really really bad at logistics because logistical issues were mostly ignored, in the cult of operational maneuver and quick decision, that outlook of the German officer corps was one that did not take logistics into account, obsessed with operational and tatics, logistics was neglected field even at the higher levels


"A further issue, one closely connected to operational thinking, was not resolved for the attack against the Soviet Union. The conduct of rapid and mobile operations absolutely required an agile, expansive, and mobile logistical system to cope with the vast area of the operations. i n the period between the world wars this core problem of German operational thinking had been suppressed by the primacy of purely operational factors, although the acceleration of the rates of advance through motorization had increased logistical requirements even more.

The transition from transportation by rail to motor vehicles that accompanied the troops in the field was still incomplete in the German Army, despite the experiences of World War i . 94 Simultaneously, the long-standing weaknesses in the German railroad system had not been corrected. 95 With only a few exceptions, Halder being among the most noteworthy, the General Staff had no great interest in logistical issues.

Although all forms of logistics had gained enormous importance in modern mobile warfare, the transfer or promotion of an officer to the branches of transport or supply—which were considered second-rate—was almost always considered a “punitive transfer” by the “victim.”

Traditionally, the operational thinking and logistics system of the German Army were adapted to the areas in Central e urope adjacent to the country’s borders. World War i exposed the limitations of this system. n onetheless, the belief was widespread that during the pending operations in the east any logistical problems could always be mastered through Germany’s vaunted improvisational capabilities. The operations experts took refuge in the idea that the suppliers ( die Versorger ) would somehow always manage to “conjure up” a logistical solution"

Page 215.
"The Myth And Reality of F German warfare - operational Thinking from Moltke the elder to Heusinger"
Gerhard Gross.

[ljadw]

I have to disagree :
The Allies were not better in logistics than the Germans : see September 1944: Patton and Market Garden .
The importance of logistics is exaggerated : better logistics does not give you victory : more fuel for Patton would not mean that he could advance to Berlin .And more supplies for Rommel would not result in the Germans being at the Canal .
Other example : it has been claimed that the Ostheer received insufficient supplies during the Winter of 1941-1942, but ,if this was true (IF ! ) ,the result was still that the Germans were holding the front and that the Soviet Winter offensive was a failure .
It has also been claimed ( IMO wrongly ) that the LW failed to supply Stalingrad and that this was the cause of the defeat of 6 th Army .
But ,if there were not enough supplies, how to explain that 6 th Army fought during 10 weeks ?
But, if there were enough supplies, how to explain that 6 th Army had to give up after 10 weeks ?

[historygeek2021]

Ok The Argument is the German Army was really really bad at logistics because logistical issues were mostly ignored, in the cult of operational maneuver and quick decision, that outlook of the German officer corps was one that did not take logistics into account, obsessed with operational and tatics, logistics was neglected field even at the higher levels


"A further issue, one closely connected to operational thinking, was not resolved for the attack against the Soviet Union. The conduct of rapid and mobile operations absolutely required an agile, expansive, and mobile logistical system to cope with the vast area of the operations. i n the period between the world wars this core problem of German operational thinking had been suppressed by the primacy of purely operational factors, although the acceleration of the rates of advance through motorization had increased logistical requirements even more.

The transition from transportation by rail to motor vehicles that accompanied the troops in the field was still incomplete in the German Army, despite the experiences of World War i . 94 Simultaneously, the long-standing weaknesses in the German railroad system had not been corrected. 95 With only a few exceptions, Halder being among the most noteworthy, the General Staff had no great interest in logistical issues.

Although all forms of logistics had gained enormous importance in modern mobile warfare, the transfer or promotion of an officer to the branches of transport or supply—which were considered second-rate—was almost always considered a “punitive transfer” by the “victim.”

Traditionally, the operational thinking and logistics system of the German Army were adapted to the areas in Central e urope adjacent to the country’s borders. World War i exposed the limitations of this system. n onetheless, the belief was widespread that during the pending operations in the east any logistical problems could always be mastered through Germany’s vaunted improvisational capabilities. The operations experts took refuge in the idea that the suppliers ( die Versorger ) would somehow always manage to “conjure up” a logistical solution"

Page 215.
"The Myth And Reality of F German warfare - operational Thinking from Moltke the elder to Heusinger"
Gerhard Gross.

Experience shows that the Germans were pretty good at logistics. They had to undertake a major overhaul and resupply of their forces in northern France after Fall Gelb in order to launch another major operation, Fall Rot, in less than 2 weeks. They managed to supply their forces all the way to Leningrad, Moscow and Rostov in 1941, and to the doorstep of Grozny in 1942. The only real logistical crisis I can think of during the war was the winter of 41/42 when their trains couldn't withstand the Russian cold. That was an egregious mistake, but it doesn't point to an overall inadequacy in logistics.

[pugsville]

Ok The Argument is the German Army was really really bad at logistics because logistical issues were mostly ignored, in the cult of operational maneuver and quick decision, that outlook of the German officer corps was one that did not take logistics into account, obsessed with operational and tatics, logistics was neglected field even at the higher levels


"A further issue, one closely connected to operational thinking, was not resolved for the attack against the Soviet Union. The conduct of rapid and mobile operations absolutely required an agile, expansive, and mobile logistical system to cope with the vast area of the operations. i n the period between the world wars this core problem of German operational thinking had been suppressed by the primacy of purely operational factors, although the acceleration of the rates of advance through motorization had increased logistical requirements even more.

The transition from transportation by rail to motor vehicles that accompanied the troops in the field was still incomplete in the German Army, despite the experiences of World War i . 94 Simultaneously, the long-standing weaknesses in the German railroad system had not been corrected. 95 With only a few exceptions, Halder being among the most noteworthy, the General Staff had no great interest in logistical issues.

Although all forms of logistics had gained enormous importance in modern mobile warfare, the transfer or promotion of an officer to the branches of transport or supply—which were considered second-rate—was almost always considered a “punitive transfer” by the “victim.”

Traditionally, the operational thinking and logistics system of the German Army were adapted to the areas in Central e urope adjacent to the country’s borders. World War i exposed the limitations of this system. n onetheless, the belief was widespread that during the pending operations in the east any logistical problems could always be mastered through Germany’s vaunted improvisational capabilities. The operations experts took refuge in the idea that the suppliers ( die Versorger ) would somehow always manage to “conjure up” a logistical solution"

Page 215.
"The Myth And Reality of F German warfare - operational Thinking from Moltke the elder to Heusinger"
Gerhard Gross.

Experience shows that the Germans were pretty good at logistics. They had to undertake a major overhaul and resupply of their forces in northern France after Fall Gelb in order to launch another major operation, Fall Rot, in less than 2 weeks. They managed to supply their forces all the way to Leningrad, Moscow and Rostov in 1941, and to the doorstep of Grozny in 1942. The only real logistical crisis I can think of during the war was the winter of 41/42 when their trains couldn't withstand the Russian cold. That was an egregious mistake, but it doesn't point to an overall inadequacy in logistics.

I Disagree totally,. and it's more than just my opinion.Gross is in the German Army, he studied this. You got anything other than just you opinion?

[pugsville]

I have to disagree :
The Allies were not better in logistics than the Germans : see September 1944: Patton and Market Garden .
The importance of logistics is exaggerated : better logistics does not give you victory : more fuel for Patton would not mean that he could advance to Berlin .And more supplies for Rommel would not result in the Germans being at the Canal .
Other example : it has been claimed that the Ostheer received insufficient supplies during the Winter of 1941-1942, but ,if this was true (IF ! ) ,the result was still that the Germans were holding the front and that the Soviet Winter offensive was a failure .
It has also been claimed ( IMO wrongly ) that the LW failed to supply Stalingrad and that this was the cause of the defeat of 6 th Army .
But ,if there were not enough supplies, how to explain that 6 th Army fought during 10 weeks ?
But, if there were enough supplies, how to explain that 6 th Army had to give up after 10 weeks ?

Well those professionals who have studied this disagree. have you got anything other than just your opinion?

The Allies planning logistics was front and center to what they were doing, with the Germans an afterthought at best. And shown throughout the Russian campaign just how bad they were.

[TheMarcksPlan]

Experience shows that the Germans were pretty good at logistics.

I'd liken it to comparing the British/US vs. German combat effectiveness. Were the Germans better? Yes. Were the British/US bad armies who ignored combat? Of course not.

The only real logistical crisis I can think of during the war was the winter of 41/42 when their trains couldn't withstand the Russian cold. That was an egregious mistake, but it doesn't point to an overall inadequacy in logistics.

Logistical crisis engulfed Ostheer in late Fall also, especially in Army Group South.

What nobody properly connects, IMO, is that Barbarossa's spectacular logistical failings were directly tied to the short campaign plan.

A similar thing recurred in latter Blau: Ostheer was logistically overextended at Stalingrad and Grozny but it's not like the Germans didn't know that. They (in this case primarily Hitler, unlike Barbarossa) simply assumed that overextension was fine relative to remaining Soviet combat strength.

Very few analysts are willing/able rationally to evaluate logistics in context of - as one element of - broader strategy. If one can rush forward against weak opposition then logistical overextension should be actively sought for strategic gain. Were it actually the case that RKKA was collapsing outside Moscow in 41 or Stalingrad in 42, to abstain from taking those objectives out of logistical purity would be strategically absurd.

German errors were strategic; logistical errors were subsidiary to strategic errors.

have you got anything other than just your opinion?

I'm putting this guy on ignore. Belligerent, rude, and superficial comments are a deadly combo. Before I do so, historygeek2021 will know what I'd like to highlight about his "evidence":

With only a few exceptions, Halder being among the most noteworthy, the General Staff had no great interest in logistical issues.

Just absurd. Nobody did more to undercut Eastern Front logistics than Halder, such as ignoring/burying Wagner's analysis of spare parts supplies and railroads. The author (and poster) are in the grips of Halder's self-serving dishonesty while writing the first version of history for the US Army.

For others - a secondary source's opinion on matters is insufficient to convince me. I will evaluate their evidence, not just their opinions.

[historygeek2021]

Well those professionals who have studied this disagree. have you got anything other than just your opinion?

The Allies planning logistics was front and center to what they were doing, with the Germans an afterthought at best. And shown throughout the Russian campaign just how bad they were.

Your original statement was:

The Germans just did not include logistics as part of their planning process. It;s every bit as bad as it sounds.

This is contradicted by the simple historical record.

It is a historical fact that the German army restored the equipment and supplies of their army after Fall Gelb in time for Fall Rot in less than two weeks.

It is a historical fact that the Germans supplied their armies all the way to Leningrad, Moscow and Rostov in 1941, and all the way to Stalingrad and Grozny in 1942.

The Germans did include logistics in their planning process. They frequently stretched their logistical situation thin for larger strategic reasons (mainly, the urgent need to knock the Soviet Union out of the war in order to turn their full attention to the USA and UK), but that does not mean that "The Germans just did not include logistics as part of their planning process." It means they took a risk. The risk failed, but Germany would have failed just the same if they hadn't taken the risk.

[ljadw]

I have to disagree :
The Allies were not better in logistics than the Germans : see September 1944: Patton and Market Garden .
The importance of logistics is exaggerated : better logistics does not give you victory : more fuel for Patton would not mean that he could advance to Berlin .And more supplies for Rommel would not result in the Germans being at the Canal .
Other example : it has been claimed that the Ostheer received insufficient supplies during the Winter of 1941-1942, but ,if this was true (IF ! ) ,the result was still that the Germans were holding the front and that the Soviet Winter offensive was a failure .
It has also been claimed ( IMO wrongly ) that the LW failed to supply Stalingrad and that this was the cause of the defeat of 6 th Army .
But ,if there were not enough supplies, how to explain that 6 th Army fought during 10 weeks ?
But, if there were enough supplies, how to explain that 6 th Army had to give up after 10 weeks ?

Well those professionals who have studied this disagree. have you got anything other than just your opinion?

The Allies planning logistics was front and center to what they were doing, with the Germans an afterthought at best. And shown throughout the Russian campaign just how bad they were.

Since generations, we are subject to an incessant propaganda offensive from mainly Anglo-Saxon historians who tell us that the Germans were not good in intelligence and logistics,which were reserved to Britain and the US and that this is ( with the decisions of Hitler ) the main reason of the German defeat .
The facts on the other hand,prove that this is not correct :
the B Dienst of the KM was as good as Bletchley Park .
the Red Ball Express was not better than the Grossraumtransport in Russia .
there are no examples in the Russian campaign of defeats/victory caused by bad logistics ( logistics being NOT the production of supplies, but the transport of supplies ) .
a lot has been written about the delay of Typhoon because of logistical problems, but the Anglo-Saxon historians remain silent about the delay of Dragoon caused by the same reasons .
if there had been a German Market Garden ( with the same result as the Allied one ) ,its failure would have been used to prove that the Germans were bad in logistics, but logistics were discarded for the failure of the real MG .
the defeat of Rommel The Great has been attributed to bad logistics ..from the Italians,while we know that the losses of the Axis convoys were marginal and, there is a deafening silence about the logistics of 8th Army .

No one denies the importance of logistics in WWII ,as in WWI ,but, its importance has been ,and is still ,exaggerated, in a lot of cases, to deny that the Soviets defeated the Germans .
The picture the public has is that the Germans lost,not that the Soviets won, and that it would have sufficed for the Germans to defeat the Soviets ( who were after all inferior people ) ,to learn the lessons of the logistical experts from DC and Whitehall .
This bias exists even today, 76 year after the events, and is stronger than before .
It was Galbraith who said in 1945 that the Allied victory (allied : limited to US and the UK ( but very secondary ) proved that their political and economic system was superior .
This is only the usual hubris of the winner.
If Germany had won, Goebbels would have said the same .

[pugsville]

I have to disagree :
The Allies were not better in logistics than the Germans : see September 1944: Patton and Market Garden .
The importance of logistics is exaggerated : better logistics does not give you victory : more fuel for Patton would not mean that he could advance to Berlin .And more supplies for Rommel would not result in the Germans being at the Canal .
Other example : it has been claimed that the Ostheer received insufficient supplies during the Winter of 1941-1942, but ,if this was true (IF ! ) ,the result was still that the Germans were holding the front and that the Soviet Winter offensive was a failure .
It has also been claimed ( IMO wrongly ) that the LW failed to supply Stalingrad and that this was the cause of the defeat of 6 th Army .
But ,if there were not enough supplies, how to explain that 6 th Army fought during 10 weeks ?
But, if there were enough supplies, how to explain that 6 th Army had to give up after 10 weeks ?

Well those professionals who have studied this disagree. have you got anything other than just your opinion?

The Allies planning logistics was front and center to what they were doing, with the Germans an afterthought at best. And shown throughout the Russian campaign just how bad they were.

Since generations, we are subject to an incessant propaganda offensive from mainly Anglo-Saxon historians who tell us that the Germans were not good in intelligence and logistics,which were reserved to Britain and the US and that this is ( with the decisions of Hitler ) the main reason of the German defeat .
The facts on the other hand,prove that this is not correct :
the B Dienst of the KM was as good as Bletchley Park .
the Red Ball Express was not better than the Grossraumtransport in Russia .
there are no examples in the Russian campaign of defeats/victory caused by bad logistics ( logistics being NOT the production of supplies, but the transport of supplies ) .
a lot has been written about the delay of Typhoon because of logistical problems, but the Anglo-Saxon historians remain silent about the delay of Dragoon caused by the same reasons .
if there had been a German Market Garden ( with the same result as the Allied one ) ,its failure would have been used to prove that the Germans were bad in logistics, but logistics were discarded for the failure of the real MG .
the defeat of Rommel The Great has been attributed to bad logistics ..from the Italians,while we know that the losses of the Axis convoys were marginal and, there is a deafening silence about the logistics of 8th Army .

No one denies the importance of logistics in WWII ,as in WWI ,but, its importance has been ,and is still ,exaggerated, in a lot of cases, to deny that the Soviets defeated the Germans .
The picture the public has is that the Germans lost,not that the Soviets won, and that it would have sufficed for the Germans to defeat the Soviets ( who were after all inferior people ) ,to learn the lessons of the logistical experts from DC and Whitehall .
This bias exists even today, 76 year after the events, and is stronger than before .
It was Galbraith who said in 1945 that the Allied victory (allied : limited to US and the UK ( but very secondary ) proved that their political and economic system was superior .
This is only the usual hubris of the winner.
If Germany had won, Goebbels would have said the same .

Gross in an officer in the German Army,

[TheMarcksPlan]

No one denies the importance of logistics in WWII ,as in WWI ,but, its importance has been ,and is still ,exaggerated, in a lot of cases, to deny that the Soviets defeated the Germans .

Never thought I'd say this but ljadw is right and perhaps insightfully so. It is not unreasonable to suggest that the British and Americans, having shirked Euopean battle for most of WW2, found in logistics a means to say they were the real military geniuses, the real heroes of the story. The savage Teutons and Slavs, who massacred each other by millions, simply lacked the sophistication to understand Western ways of war. It's a way to hide the fact that the Anglo-Americans walked into the terminal stages of a fight primarily between others, knocked a few exhausted heads, and claimed most of the spoils. ...and have based a great deal of their (at least of American) claims to imperial hegemony and moral righteousness on this "great effort" ever since.

The "we're really good at logistics" narrative is a sort of consolation prize demanded by the peevish children who inherited Empire and wanted its Glory. War is, the American state would like to say, little different from efficient capitalist management (see Donald Rumsfeld).

Yet even in their own imperial (mis)adventures, the Americans have found their greatest military commanders in those who bucked the Quartermaster's dictatorship, such as James Mattis, of whom it's been noted:

His “Log [logistics] Light” configuration for the division was meant to get people north, fast, and not try to shoot our way through every little town on the way. As only he could do, he described it thus: “If you can’t eat it, shoot it, or wear it, don’t bring it.”

...that tracks the Halder/Guderian/etc approach to Barbarossa (except Mattis accurately diagnosed Iraqi strategic depth whereas Halder did not re Soviet - but again that's a strategic decision with logistical implications rather than ignorance of logistics). Mattis's way of war is also the antithesis of American warfare in WW2, which emphasized bringing everything in case we needed it, causing excessively-large division slices and a US army that, despite vast resource advantages, probably couldn't have defeated the German (let alone Soviet) army one-on-one until the closing weeks of the war.

The era of total war ended with WW2, thank god. For the liberal democracies, it ended in 1918. Thank god for the Soviet Union.

[Avalancheon]

TheMarcksPlan, do any of your posts in this thread go into detail about how the extra 5 Panzer and 5 Motorised Divisions would be created? This is the crux of your entire argument for a strengthened Invasion. Creating a new Panzer Division was not a trivial matter, though.

The Germans had to disband 2 Motorised Divisions and 4 Infantry Divisions in order to provide the Infantry and Artillery component for these new Panzer Divisions. Even harder was creating the Panzer component.

6 of the 10 new Panzer Divisions created in 1940 were formed by removing a Panzer Regiment from one of the old Panzer Divisions. But the remaining 4 Panzer Divisions had to be based around Replacement Panzer Regiments/Battalions.

The reason why the Germans had to resort to this expedient is unclear. In theory, the 10 old Divisions should have enabled the creation of 10 new Divisions. But that did not prove practical in the end. In your own words, how should the additional 5 Panzer Divisions be formed?

[TheMarcksPlan]

TheMarcksPlan, do any of your posts in this thread go into detail about how the extra 5 Panzer and 5 Motorised Divisions would be created? This is the crux of your entire argument for a strengthened Invasion. Creating a new Panzer Division was not a trivial matter, though.

The Germans had to disband 2 Motorised Divisions and 4 Infantry Divisions in order to provide the Infantry and Artillery component for these new Panzer Divisions. Even harder was creating the Panzer component.

6 of the 10 new Panzer Divisions created in 1940 were formed by removing a Panzer Regiment from one of the old Panzer Divisions. But the remaining 4 Panzer Divisions had to be based around Replacement Panzer Regiments/Battalions.

The reason why the Germans had to resort to this expedient is unclear. In theory, the 10 old Divisions should have enabled the creation of 10 new Divisions. But that did not prove practical in the end. In your own words, how should the additional 5 Panzer Divisions be formed?

I'm going to assume this question doesn't regard production issues - if it does I can refer to many, many posts on that topic.

To clarify, what is "this expedient"? Using training battalions rather than splitting all ten original panzer divisions? I'll assume so for now.

It was feasibly the case that using the training battalions was the default choice and splitting the expedient, rather than the other way around. Going into 1941, Germany probably believed its long-term force generation requirements would be lower after a quick Barbarossa than they had believed in advance of a prudently-planned French campaign (ie their army force generation plan was scheduled to peak in latter 1941). They therefore could operationalize "surplus" Ersatzheer resources.

So the short answer is you split the other panzer divisions, unless there's some direct evidence that wouldn't have worked.

For the infantry components you use other existing ID resources, as done historically. You raise substitute infantry resources via some of the ~80k more men inducted into Heer. OTL Germany raised many good divisions between France and Barbarossa , of the 11th-14th waves, so this requires nothing novel of the Ersatzheer.

[Avalancheon]

I'm going to assume this question doesn't regard production issues - if it does I can refer to many, many posts on that topic.

To clarify, what is "this expedient"? Using training battalions rather than splitting all ten original panzer divisions? I'll assume so for now.

It was feasibly the case that using the training battalions was the default choice and splitting the expedient, rather than the other way around.

What makes you so sure? Wouldn't the Germans have preferred to use existing formations that had already proven themselves in combat, rather than using untested training formations? The divisions themselves may have been cobbled together from different formations, but they were all based upon trained and experienced personnel.

Going into 1941, Germany probably believed its long-term force generation requirements would be lower after a quick Barbarossa than they had believed in advance of a prudently-planned French campaign (ie their army force generation plan was scheduled to peak in latter 1941). They therefore could operationalize "surplus" Ersatzheer resources.

So the short answer is you split the other panzer divisions, unless there's some direct evidence that wouldn't have worked.

All 10 of the old Panzer Divisions were originally composed of 2 Panzer Regiments. But after the creation of the 10 new Panzer Divisions, none of them retained a 2nd Panzer Regiment. Moreover, the Germans were apparently splitting up the Regiments themselves, in order to change their composition from 3 to 2 Battalions.

Half of the 20 Panzer Divisions had 3 Battalions, while the other half had 2 Battalions. Thats seemingly why the Germans had to resort to the Replacement Panzer Regiments/Battalions. They couldn't generate enough cadres from the existing Panzer Divisions, despite what the math would suggest. There might not actually be enough Panzer Battalions for them to form 5 new Panzer Divisions.

For the infantry components you use other existing ID resources, as done historically. You raise substitute infantry resources via some of the ~80k more men inducted into Heer. OTL Germany raised many good divisions between France and Barbarossa , of the 11th-14th waves, so this requires nothing novel of the Ersatzheer.

Providing the Infantry and Artillery component is the easy part. The final two Panzer Divisions (19th and 20th) were formed from one Infantry Division (the 19th) and two Replacement Panzer Regiments. This is probably the most economical way to create a new Panzer Division, without raising them from scratch.