December 13th, 1942 (SUNDAY)
UNITED KINGDOM: Bletchley Park: The U-boat Enigma cipher has been cracked. Shark had baffled the codebreakers from the beginning of this year because of the additional rotor which it uses. Now the Admiralty's submarine tracking room will once more be able to route convoys round the wolfpacks. Sadly, Captain Roger Winn, who runs the submarine tracking room, has collapsed and has been ordered to take sick leave.
The first German wartime naval Enigma machine (M3) was identical to the model used by the German Army and Air Force, but it was issued with additional rotors, VI, VII and VIII, which were reserved for the Kriegsmarine (German Navy). However, the Kriegsmarine also employed codebooks to shorten signals as a precaution against shore high-frequency direction-finding, and some manual ciphers. The most important codebooks were the Kurzsignalheft (short signal book) for reports such as sighting convoys, and the Wetterkurzschlüssel (weather short signal book) for weather reports. Naval Enigma signals used different ciphers, each with its own daily key (rotor order, ring settings, plugboard connections and ground setting). The principal cipher was Heimisch (Heimische Gewässer - known to Bletchley Park as Dolphin) for U-boats and surface ships in Home Waters, including the Atlantic. At least 14 other naval Enigma ciphers were used later in the war. The British codebreakers at Bletchley Park, Buckinghamshire, England, received an Enigma machine and rotors I to V from the Polish Cipher Bureau in August 1939. Marian Rejewski, an outstanding Polish cryptanalyst, had reconstructed the wiring of rotors I to III at the end of 1932 using mathematical techniques, and the wiring of rotors IV and V before the war began. The British recovered rotors VI and VII from the crew of U-33 on 12 February 1940, while rotor VIII was captured in August 1940. The British broke Dolphin cryptanalytically from August 1941 onwards. A massive reverse was encountered on 1 February 1942 when a new Enigma machine (M4) came into service on Triton (codenamed Shark by the British), a special cipher for the Atlantic and Mediterranean U-boats. The combination of M4 and Shark proved devastating. Bletchley Park became blind against Shark for over ten months. Fortunately, M4's fourth rotor (beta) was not interchangeable with rotors I to VIII. Beta increased M4's power b y a factor of 26, but rotors could still only be mixed in 336 (8x7x6) different ways - not 3,024 (9x8x7x6). At one setting of beta, M4 emulated M3, which was M4's undoing. Three members of the British destroyer HMS Petard (G 56) seized the second edition of the Wetterkurzschlüssel from U-559 on 30 October 1942, before it sank near Port Said, Egypt. The U-boats were using M4 in M3 mode when enciphering the short weather reports. On 13 December 1942, Bletchley teleprinted the OIC the positions of over 12 Atlantic U-boats, on dates from 5 to 7 December, as established from Shark weather signals. M4 had been penetrated with the help of the weather broadcasts broken at Bletchley Park. Intelligence from Shark, although sometimes badly delayed, played a critical part in the Battle of the Atlantic, perhaps saving from 500,000 to 750,000 tons of shipping in December 1942 and January 1943 alone.
Jews observe a day of mourning for their European brethren persecuted by the Nazis.
FRANCE: VICHY FRANCE: The premier, Pierre Laval, Minister of Foreign Affairs, Minister of the Interior, and Minister of Information, holds a press conference and again predicts that Germany will win the war, saying that the only alternative is to be ruled by Jews and Communists." He concludes by announcing: "I must say without any ambiguity that I want Germany's victory."
During the day, RAF Bomber Command dispatches four (A-20) Bostons and four Mosquitos on railway marshalling yard attacks in France and Belgium but only two Mosquitos bomb, one each at Laon and Criel.
During the night of 13/14 December, one each RAF Bomber Command Wellingtons lay mines off Lorient and St. Nazaire on the Bay of Biscay.
NETHERLANDS: Amsterdam: It is announced that Anton Mussert, head of the Dutch Nazis, had been appointed Fuhrer for Holland following a visit to German Chancellor Adolf Hitler's headquarters in the Soviet Union. Dr. Arthur von Seyss-Inquart remained the supreme authority. (In the nature of a probationary leader to see if, he can bring the Netherlands people nearer to Naziism. Reluctance to make Mussert a full-fledged Premier is thought to be an indication that the Nazis had learned their lesson in Norway. Mussert is one of the founders of the Dutch Fascist Party and he also founded the all-Dutch volunteer SS unit, the SS-Freiwilligen-Legion Niederlande, in 1941. (Andy Etherington)
GERMANY: Propaganda minister Joseph Goebbels records in his journal his contempt for the Italians' treatment of Jews in Italian-occupied territories. "The Italians are extremely lax in their treatment of Jews. They protect Italian Jews both in Tunis and in occupied France and won't permit their being drafted for work or compelled to wear the Star of David." But in the earliest days of fascism, Italian dictator Benito Mussolini had denied any truth to the idea of a "pure" race and had counted Jews among his close colleagues-and was even a Zionist! But with Italy's failing fortunes militarily, Mussolini needed to stress the Italians' "superiority" in some sense, and so began to mimic many of the racial and anti-Jewish legislation of the Nazis. Nevertheless, Mussolini never had the stomach-or the conviction-for the extremes of Goebbels, Göring, and Hitler. And certainly the majority of the Italian people never subscribed to the growing anti-Semitic rhetoric of the regime. In fact, the Italians refused to deport Jews from Italy-or from Italian-occupied Croatia or France-to Auschwitz.
MEDITERRANEAN SEA: Sloop HMS Enchantress (L 56) is acting as escort for convoy KMS-4 Gibraltar/Algiers. About 165 nautical miles (306 kilometers) northeast of Algiers, Algeria, in position 38.58N, 05.07E., she engages the Italian submarine R. Smg. Corallo (Captain Guido Guidi) with her depth charges the Corallo was forced to the surface. Then some reports claim the gun crew tried to bring her deck gun into action against the Enchantress. Next the Enchantress rammed Corallo sinking her with all hands lost.
LIBYA: The British 8th Army captures Mersa Brega as Rommel begins to pull out of the El Agheila positions, leaving rear guards and numerous mines to delay British pursuit.
Italian armour from the three divisions of 20th Corps now regrouped as Ariete Tactical Group, reinforced by a battle group from the newly arrived Centauro armoured division, are attacked by the British 8th Armoured Brigade, attempting to push around the desert flank. This comes at a particularly bad moment, since a large part of the German armour is temporarily immobilized while awaiting refuelling. The fight begins when a rearguard of three M14 tanks supported by four guns is attacked by 80 Shermans. The Italians hastily fall back, but when the British reach the main Italian defense line, it is they in turn who are surprised, losing numerous vehicles to the Italian guns. After a heavy artillery barrage, the British advance again. The fighting is furious, and often at close quarters. One British tanker describes how an unseen Italian artillery piece held its fire until a Crusader tank from his unit was within 50 yards of the gun position. However, the Italian gunners' first shot was just off, tearing through the storage boxes on the side of the vehicle, after which the Crusader drove at full speed straight over the Italian emplacement, crushing one of the gunners under its treads. Another tank in the same unit was less lucky, taking a direct hit that killed the driver and mangled the commander's arm and leg. Later 12 M14s counter-attacked, but the Shermans knocked out eight in an extended fight. After this the British advance overcame the Italian antitank screen, destroying or capturing a dozen 47mm guns and taking 50 prisoners. But the British, having lost 22 tanks and two armoured cars, with night descending established a defensive lager as per their usual procedure, allowing the Italians to pull back unmolested. (Mike Yaklich)
RAF aircraft and P-40s of the USAAF Ninth Air Force fly strafing and bombing missions against German ground forces which begin withdrawing from El Agheila during the early morning.
TUNISIA: Bizerta and Tunis are the targets of heavy US air strikes.
V Corps, British First Army, is ordered to be prepared to renew the drive on Tunis. The lull ensues as preparations are made for attack.
Fifteen USAAF Twelfth Air Force B-17 Flying Fortresses bomb the harbor and docks at Tunis. Over Bizerte, ten B-17s bomb the harbor and docks; they are followed shortly by 19 B-24 Liberators which are detached from the USAAF Eighth Air Force in England, that attack the same targets. Meanwhile, six B-25 Mitchells bomb the harbor area at Sousse while B-26 Marauders blast a bridge north of Sfax; P-38 Lightnings escort both missions. Other P-38s attack several targets including vehicles north of Gabes and a schooner off Cape Dimasse. In other action, P-38 Lightnings, P-40s and USAAF Spitfires fly reconnaissance and patrols over much of Northwest Africa and C-47 Skytrains fly 17 transport missions between various points in Northwest Africa.
NEW GUINEA: In Papua New Guinea, further futile efforts are made to supply the roadblock on the Soputa-Sanananda trail, which is now out of contact with the rest of front. Buna Village is subjected to heavy fire in preparation for an attack on 14 December; after nightfall, the Japanese garrison, now reduced to about 100 men, evacuates the village and swims for Giruwa. Corvettes return to Oro Bay under cover of darkness and finish unloading Australian troops.
In Papua New Guinea, a Japanese convoy of five destroyers, bringing some 800 men (among them Major General ODA Kensaku, General HORII's successor as commander of South Seas Detachment), is detected off Madang while proceeding toward the beachhead and unsuccessfully attacked by Allied planes. USAAF Fifth Air Force B-17 Flying Fortresses and B-24 Liberators attack as it moves south but fail to deter its progress. Meanwhile A-20 Havocs bomb and strafe the Cape Killerton area while B-17s bomb the Salamaua area.
SOLOMON ISLANDS: On Guadalcanal, the Army's 3d Battalion, 182d Infantry Regiment and Company C of the 2d Marine Engineer Battalion arrive.
BISMARCK ARCHIPELAGO: USAAF Fifth Air Force B-26 Marauders hit Gasmata Airfield on New Britain Island.
TERRITORY OF ALASKA: ALEUTIAN ISLANDS: A largely negative reconnaissance is flown by the USAAF Eleventh Air Force over Attu, Agattu, Kiska, Amchitka and the Semichis Islands by two B-24 Liberators and two P-38 Lightnings.
U.S.A.:
Submarine USS Muskallonge launched.
ATLANTIC OCEAN: