Germany discovers Ultra and Enigma hack

Deleted member 94680

Changing the Enigma machine is simple.

So why didn’t they do it more often?

Changing user behavior is hard.

No it’s not. In the military we have these things called “orders” - if you want people to do a certain thing (or stop doing a certain thing) you put out a set of “orders” and generally speaking the vast majority of your military personnel do (or stop doing) that certain thing. Those that don’t can be reprimanded or even jailed if they fail to change their behaviour.

You're going to need to convince every mid-grade Heer, Luftwaffe and Kriegsmarine officer to put one of his better officers onto cipher duty, and rotate them out once they start getting too cocky.

Exactly, you’re going to have to be professional about it.

You'll need to make sure said officer doesn't train his replacement by sending a bunch of dummy messages.

Yes, you’ll need procedures that don’t help the enemy to break your cypher.

You'll need to deal with the blowback of said mid-grade officer's bosses saying 'This crap is only happening because B-dienst don't believe in their own equipment.'

Then the Admiral running your intelligence service will have to clamp down on that sort of behaviour.

And if you're really unlucky, seeing as how you just admitted Enigma was worthless, Hitler will get the idea in his head that poem codes should be used.

You haven’t admitted it was worthless, you’ve admitted there are procedures to follow to keep its efficiency. That there are ‘offensive’ and ‘defensive’ actions to be taken in this sphere of military activity just as there are in all other spheres.

What I actually meant is things more like use it less, don’t use it to transmit a weather report prefaced with a word-for-word identical opening praising der fuhrer every day (IIRC), accept it might get compromised and plan accordingly.

Just because OTL the Germans were terrible at it, doesn’t mean it’s impossible to be better.
 
That is interesting, I must admit I never knew that. Can you provide any more details on the encryption system the Italians used?


making some further research, well Ultra broken the code of the italian air force in early 41, so it was not really necessary know what Regia Marina will do as it can easily extrapolate by the message of the air force.
BTW Regia Marina used a version the C-38 (M-209 for the US Army)
 
Replacing enigma would be a major headache, as you'd have to produce literally thousands of machines, transport them all, and make sure none were nicked off with along the way. The British were rather good at disguising raids to gain enigma workings to look like more general raids, and it only takes one such raid to break your new system wide open...
 
The U-boats can still use radio messaging from aerial reconnaissance to coordinate, they just can’t reply back.

So the B.d.U. says "hey, let's have 59, 215 and 307 converge from three sides on that convoy!". And they issue the orders. Only, they don't know for a fact that none of those three subs has been sunk. Or has finished its torps. Or is snailing back to base after taking damage. Or is entirely out of position because it has spent 20 hours evading a stubborn destroyer. The B.d.U. just issues orders assuming all three are in position, operational and ready to play their part in the scheme.
 
In some respects it might benefit the Allies. Twice Eisenhowers staff were blinded by a over reliance on IULTRA sourced intel. The first was the 'Morning Ar' offensive March 1943 in Tunisia. Kesselrings command settled all the planning and coordination by face to face meetings & telephone. The Brits picked up nothing via radio/Enigma. The result was Rommels attack crushing the US 1st Armored Div with a four division attack and driving on to the Kasserine Pass.

The second was the Ardennes offensive. again none of the planning or preparation message traffic went by radio. Without Enigma the Allied intelligence is forced to make better use of other sources. In both these cases there were strong clues collected by patrols, prisoner interrogation, air reconissance, ect... but the intel officers and staff were over focused on the ULTRA originated intel.

The Luftwaffe was the worst at Enigma security, poor operator discipline, & overuse by command staff made it the best source for operational intel in land battles. Unlike the Navy the air and ground forces did not make a wholesale conversion to four rotor machines, sticking with the three rotor. Internally in Germany some of the military administrative agencies kept the antique two and single rotor machines in use. Those messages were useful in evaluating German industrial production, and the effects of bombing.

Probablly the best use of the UTRA system was the highest level traffic. Analysing that, the Deception Committiee was able to track the effects of the deception operations and fine tune them in real time to fit Hitlers current thinking. losing Engima would reduce the effectiveness of the many deception operations underway.

Wavell admitted the same after the war.

He was reliant on Ultra sharing Rommel's missives to his superiors asking for more kit and men and stuff etc by lying to them about how weak the Axis forces were - and this dictated the subsequent activities of Wavell's army in allowing the experienced units to pull back to rebuild and refit, sending W force to Greece and leaving what was effectively an understrength light screen in Cyrenaica. Wavell believed that Rommel and the Italians would not be able to attack until several months after they actually did - by which time his army would have been far better prepared.

Had he not had the Ultra intercepts he might have been far more conservative regarding letting forces go to Greece etc (and Whitehall might have been the same).
 
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