Interdiction WWII Part VI - Northwest Africa November 1942-May 1943

In the early days of the Tunisian Campaign Allied air commanders had tried to attack enemy merchantmen in port. They soon found that the turnaround time of the B-17s was too slow. Poor though the facilities of the Tunisian ports were, many convoys unloaded and put to sea before a strike could be mounted. Occasionally, B-17s attacked shipping at sea, but their slow turnarounds and inaccurate bombing thwarted attempts to catch convoys in midpassage. B-26 medium bombers attached to the Coastal Air Force therefore became the chief weapon of the aerial antishipping campaign. The airfields to support their operations were ready by February 1, 1943, but three weeks of bad weather over the Strait of Sicily delayed operations. The Marauders almost always attacked ships at sea because they had suffered heavy losses earlier when they braved the heavy antiaircraft defenses of Tunis and Bizerte. At first they employed a skip-bombing technique developed in the Pacific: The flyers approached their prey abeam and at low altitude, releasing their bombs so that they caromed from the surface of the sea into the sides of the targeted vessels. The tactic was at first highly effective, but was defeated when heavier antiaircraft armament on the merchantmen forced the bombers to attack from about 10,000 feet. From this altitude bombing accuracy was abysmal. The aviators then resorted to attacking in staggered flights at low and medium altitudes in an attempt to divide and confuse the antiaircraft gunners. These attacks, one pilot recalled, were “never entirely successful.” Toward the close of the campaign a weakening of antiaircraft fire permitted a return to skip bombing; at this stage, the weakness of the Luftwaffe permitted employing as dive bombers the P-38s originally detailed to escort the B-26s. The B- 26s were aided by British aircraft from Malta, which now used against Tunisia-bound convoys the deadly skills they had honed attacking the Libyan convoys. Royal Air Force Malta, which had been placed under Tedder’s operational control, used two kinds of aircraft for antishipping operations: the Albacore torpedo-bomber and the versatile Beaufighter.

Despite the difficulties posed by antiaircraft fire and a late start, the antishipping campaign was eminently successful in reducing the flow of supplies to Heeresgruppe Afrika. The Allies learned from ULTRA that of all the merchantmen that set sail for Tunisia in March, nearly half had been sunk-but a fifth had been lost in February. Because of the shortage of ships and general derangement of its logistical system, during the critical months of March and April the Axis was able to load only 140,572 tons of supplies for Tunisia. This equates to a barely adequate average monthly shipment of 70,286 tons, which was then subjected to a frightful loss rate. In April, 41.5 percent of all cargos were lost. This was slightly less than the percentage lost in March, but in April only 29,233 tons of supplies reached Tunisia-March’s figure had been 43,125. Of the vessels lost in these months, aircraft claimed about two-thirds. By the end of April, Admiral Friedrich Ruge, sent to Rome to expedite the flow of supplies to Africa, had come to agree with the conclusion reached some time before by the Italian Navy-that the losses on the run to Tunisia had become so great that they could no longer be justified by Heeresgruppe Afrika’s slim chance for survival. Berlin, however, continued to insist on throwing good money after bad.

The effect of the curtailed flow of supplies on the German and Italian forces in Tunisia was great. Even before the interdiction campaign became effective, their logistical position was weak. On February 13, Rommel’s quartermaster reported that he had not received enough supplies to cover consumption; the shortage of ammunition was critical when the attack through the Kasserine Pass began the next day. With the beginning of serious interdiction in late February, the logistical position of the Axis’ armies grew steadily worse. In early March, Rommel was still able to mount the Axis’ last offensive of the campaign. He struck at the advancing Eighth Army near Medenine, only to be repelled with heavy losses in tanks. Thereafter, the fortunes of Heeresgruppe Afrika declined rapidly. By the end of March, Montgomery had outflanked the Mareth Line, forcing the Germans to retreat north up the coast and to yield the ports of Sousse and Sfax. At this point the ailing Rommel left Africa, never to return. Von Arnim succeeded him as commaqder of Heeresgruppe Afrika. On the western front the First Army began a sustained offensive that by March 17 succeeded in capturing Gafsa. Not far from there, the two Allied armies linked up on April 7; four days later the First Italian Army joined the Fifth Panzerarmee. As the Tunisian Campaign entered its last month the forces of the Axis were completely hemmed in a small bridgehead defined by a front that stretched 100 miles from Cape Serrat just west of Bizerte to Enfidaville southeast of Tunis.

Heeresgruppe Afrika lacked the fuel and ammunition to counter the final Allied offensive. It reported on March 28 that it had entirely depleted its reserves of both commodities. On April 1 the quartermaster described the logistical situation as “very bad.” On April 10 the Allies intercepted a message that told of an armored division that for want of fuel had abandoned its equipment and retreated on foot.

From the earliest days of the Tunisian Campaign, the Germans had attempted to compensate for their inadequate supply of shipping by the extensive use of air transport. Nine groups of Ju 52 transports-468 aircraft- carried urgently needed supplies, particularly fuel and ammunition. They were aided by thirty large six-engine Me 323 transports. On some days as many as 585 tons were ferried across the Strait of Sicily, although the average appears to have been close to 172 tons a day. The Allies knew the details of the airlift from ULTRA, but the same problems that delayed antishipping operations stayed action against the German airlift. Strategic considerations dictated further delay. The assault upon the aerial convoys, Operation FLAX, was planned in early February but not implemented until April. FLAX was a card that could not be played more than a few times, as shown by the relative impunity with which the surviving Axis transports operated at night after the trap had been sprung. The flight time across the Strait of Sicily was so short that interception could be made only with precise intelligence. The Germans, understanding this but not knowing that their codes had been compromised, operated by day. Since their enemy had the option of flying by night, the Allies delayed implementation of FLAX until the most German transport aircraft were in operation so that the blow would be as decisive as possible. They also wanted to destroy the transports when they were most needed, and therefore timed FLAX to coincide with both a high point of the antishipping campaign and the final assault on Tunis.

The transport aircraft were mostly based at fields near Naples and Palermo; a few staged from Bari and Reggio di Calabria. Flights usually began at Naples and proceeded after stops in Sicily to the main Tunisian terminals, Sidi Ahmed and El Aouina. Occasional flights went directly to Tunisia, picking up their escorting fighters over Sicily.68 FLAX called for fighters to intercept the aerial convoys over the strait. There were also bombing attacks on the overcrowded staging fields in Sicily and unusually ambitious antishipping sweeps. On April 6 P-38s intercepted a large formation of Ju 52s a few miles from the Tunisian coast while bombers attacked airfields in Sicily and Tunisia. Further attacks on aerial convoys followed on April 10, 11, 18, and 19. These resulted in the destruction of about 123 Ju 52s and 4 Italian SM 82s. On April 22 an entire convoy of twenty-one Me 323s was destroyed; two of these giants had been destroyed earlier for a total loss of twenty-three. Thereafter reduced numbers of Ju 52s flew at night. FLAX dealt the German air transport fleet a blow from which it never recovered-and ended Heeresgruppe Afrikds last chance for any significant resupply of its rapidly dwindling supply of fuel.

Having been prevented by logistical problems from employing the strategy that might have permitted a prolonged stand in Africa, Heeresgruppe Afrika was in its last days hard put to defend itself at all because of crippling shortages of ammunition and, especially, of fuel. Near the end, von Arnim had been able to move his headquarters only because of the providential discovery of a drum of aviation gasoline on a beach flotsam, presumably, from one of FLAX’S victims. He surrendered himself and his army on May 12, having with his own hands set fire to his headquarters caravan.

The Tunisian Campaign affords a clear example of the decisive importance of logistics in modern warfare. In Tunisia, and North Africa generally, the Axis had usually prevailed when it met its foes on anything like equal terms. Heeresgruppe Afrika was neither outfought nor outgeneraled; starved of supplies, it yielded at length to the superior numbers of a lavishly equipped enemy. “The final decision was fought out on the ground,” a German study concluded, “but the effect of the air war on supplies and morale had already determined the outcome of the battle.” As Kesselring had foreseen, supply had indeed been “everything.”

The great success of the Allies in Tunisia had several consequences. It represented a triumph for the three-stage concept of aerial operations that the British had developed in the eastern desert. For the rest of the war, the basic pattern for Allied combined arms offensives remained air superiority, interdiction, and close air support for the ground forces. Tunisia also saw final acceptance of the idea that the control of air power in a theater of operations should reside in a single commander, equal in authority to the ground commander with whom he worked closely in executing the plans of the theater commander. This organizational conception, together with the three-stage concept of aerial operations, was in the summer of 1943 written into FM 100-20, Command and Employment of Air Power, which many airmen regarded as a virtual charter of independence from the ground forces.

So powerful an argument was the victory in Tunisia for the centralization of air power and the coequal status of air commanders with those of the ground forces, that some American airmen came perilously close to attributing the Allied victory in Northwest Africa entirely to the triumph of their views in the reorganizations of December 1942 through February 1943. But however fruitful the organizational changes of February 1943 might have been, the primary reasons for the success of Allied interdiction are to be found elsewhere. The material advantage of the Allied air forces was ultimately so crushing that it is difficult to see how the Anglo-Americans could have failed once they dealt with their problems of inadequate supply and improved their airfields. The Axis’ logistical system was inherently inadequate. Too few suitable ships remained to Italy by 1943 to support Tunisia adequately; the loss of a comparatively small number of vessels therefore quickly pitched Heeresgruppe Afrika into logistical crisis. There was, moreover, a strategic asymmetry between belligerents that greatly favored the Allied side: The Axis’ supply lines were open to attack while those of the Allies were virtually exempt because of Germany’s lack of strategic bombers. The Anglo-Americans were therefore able to go on the offensive even before they had general air superiority over Tunisia. The Luftwaffe was forced to divide and redivide its aircraft in an ultimately futile attempt to protect convoys, ports, and airfields from a foe who could usually concentrate his aircraft to win local air superiority. From ULTRA, finally, Tedder and his colleagues had essentially complete information about the movements of the enemy’s convoys through the constricted channels in the minefields of the Strait of Sicily.

Interdiction WWII Part V - Northwest Africa November 1942-May 1943

The Germans and Italians launched a series of limited offensives in January and February to bloody Eisenhower’s forces before the formidable Eighth Army arrived from the east. In January, von Arnim’s Fifth Panzerarmee faced Anderson’s First Army in western Tunisia, while in the south the First Italian Army awaited the pursuing Montgomery. The heart of the First Italian Army’s position was the Mareth Line, a heavily fortified position, constructed by the French before the war against an Italian attack from Libya. It ran from the inland mountains through the town of Mareth to the sea, athwart the coastal plain that was the only route of advance for a large force. In late January, the Fifth Panzerarmee inflicted stinging setbacks on the British and French in a series of limited attacks near the towns of Ousseltia and Faid. The next month, von Arnim attacked the British through the Faid Pass toward Kasserine while Rommel, with the First Italian Army, struck at Gafsa through the Kasserine Pass. The inexperienced American I1 Corps retreated in disarray until it managed to make a stand at Thala. Rommel then withdrew back through the Kasserine Pass to resume his position on the Mareth Line. Von Arnim’s offensive also petered out, and by March 1 the Allies had recovered their original positions.

Even as they repulsed the Axis’ desperate thrusts, the Allies began to implement the strategy that in barely more than two months would result in their conquest of Tunisia. Not surprisingly, given the presence of both Coningham and Tedder, it was closely based on the three-stage model for a combined arms offensive developed in the Egyptian desert. The first task the Allies set for themselves was to wrest air superiority from the Axis. While still fighting for command of the air, the Anglo-Americans planned to turn their attention to the vulnerable convoys that plied the Strait of Sicily. An all-out offensive was planned for early May to destroy Heeresgruppe Afrika once it had been weakened logistically and denuded of air support.

Coningham set forth his plans for winning air superiority in an operations directive of February 10, 1943. He called for “a continued offensive against the enemy in the air” and “sustained attacks on enemy main airfields.” The attacks on the airdromes fell by day to strafing fighters and large formations of light and medium bombers, occasionally helped by heavy bombers from the Strategic Air Force. Light bombers, acting singly or in small formations, pressed the attack by night. The Germans noted with some surprise that in February and March the Allies began to place so much emphasis on counterair operations that they stinted on close air support for their ground forces.

German airfields in Sicily were inherently vulnerable: No radar protected them from surprise attack, and their coastal locations precluded antiaircraft defense in depth. Towns and olive groves, moreover, hemmed in the fields so that parked aircraft could not be dispersed properly. German airfields in Tunisia did permit adequate dispersion, and radar and observers protected them against surprise attacks. But incessant Allied air attacks forced the Germans to divide their aircraft among many small fields, which led to a considerable loss of efficiency.

The counterair campaign forced the Luftwaffe to devote a considerable portion of its strength to defending its bases: “Even the taking-off at the air bases,” a German study noted, “could often only be done with fighter protection. The forces set aside for safety measures had to be proportionally The Luftwaffe could ill afford this diversion of aircraft, for Allied air strength was growing rapidly while the Germans, short of industrial capacity and beset from other quarters, could barely replace their losses. While they had begun 1943 with more aircraft (690 combat aircraft) in and around Tunisia than the Allies (480 combat aircraft), their position deteriorated as the Anglo-Americans began to overcome their problems with basing and supply. The improvements permitted the Allies to fly into the combat zone not only aircraft that they had had to leave at Gibraltar or in Algeria but many new ones from Britain and the United States. By March 21 the two principal components of the Northwest African Air Forces-the Tactical and the Strategic Air Forces-disposed 1,501 combat aircraft, while German strength had risen not at all. At the end of the Tunisian Campaign (May 13), it was about what it had been in January-695 combat aircraft.

An interesting feature of the Tunisian Campaign is that the Allies were able to begin telling attacks on the Axis’ lines of communication before they had won general air superiority. Allied and German sources concur that the period of Allied air superiority over Tunisia began about April 1, while Allied aircraft had been regularly attacking the Axis’ convoys and ports since late February. This the Allies had been able to do because the Luftwaffe had to fight under a serious strategic disadvantage: Once the Allied air forces were established in Tunisia, the Axis’ lines of communication were wholly vulnerable, while those of the Allies remained largely exempt from retaliation. German aircraft based in Sicily and Sardinia tried to attack the Allied ports in Algeria and Morocco- Port Lyautey, Bdne, Oran, and Algiers-that sustained Eisenhower’s command, but their lack of range and ordnance-carrying capacity restricted them. No German fighters had the range to accompany the bombers, and when the Allies emplaced strong air defenses, the raiders’ losses quickly became insupportable. The same problems hobbled German efforts to attack Allied convoys. Even before the Allies had a numerical preponderance, the strategic asymmetry seriously disadvantaged the Luftwaffe, for the Allies, having comparatively safe supply lines, could mass their aircraft to win local air superiority. Lacking aircraft in numbers sufficient to contend for air superiority and to defend their convoys, the Germans had to concentrate upon protecting their vital supply lines. By conceding air superiority in this way, they facilitated the attacks on their air bases that progressively reduced their ability to provide air cover for the convoys.

On February 19, 1943, Eisenhower observed that the enemy was receiving about 75 percent of his requirements. “The termination of the Tunisian campaign,” he observed, “depends on the extent to which we can disrupt enemy lines of communications.” Tedder specified the priorities of the antishipping campaign in an operational directive of March 7, 1943, ordering that the “normal mission” of even the “strategic striking forces” was “the air attack of Axis sea, land and air lines of communications and supply to and from Tunisia.” Ships were the target of first priority. Tedder assigned the greatest importance to tankers traveling between Sicily and Tunisia. He ranked tankers sailing between Italy and Sicily next, and then freighters bearing military supplies. Ports followed ships in importance. The greatest priority went to Tunis and Bizerte, then came the other Axis-held ports in North Africa; the Sicilian ports of Palermo, Messina, and Trapani; and the Italian port of Naples.

The bombing of ports in Italy, Sicily, and North Africa fell to American heavy bombers-B-17s of the Twelfth Air Force and B-24s of the Libya-based Ninth Air Force. These attacks destroyed ships and supplies outright. Their chief effects, however, were to make an already marginal logistical system still less efficient and to expose the convoys to greater perils at sea. At Tunis and Bizerte the heavy bombers periodically destroyed or damaged the cranes used to unload the ships; they so demoralized the native laborers who manned the ports that eventually the importation of stevedores from Germany became necessary. A ship of 1,500 tons required a full day to unload, and a vessel of 5,000 tons required three days. This slowed down the turnaround time of convoys, thereby reducing the capacity of the system as a whole.

Kesselring’s optimism about supplying Tunisia had been based largely on the fact that the sea route from Italy to Tunisia was only about a third as long as that between Italy and Libya. Ships sailing to Tunisia would therefore be less exposed to air attack. They could also be protected from the Royal Navy by the very extensive minefields of the Strait of Sicily, the last of which was laid in the winter of 1942-1943. The original plan for supplying Tunisia had sought to take advantage of this protection by transporting supplies the length of Italy by rail and then ferrying them across the narrow and easily defended Strait of Messina to Sicily. At Palermo and other Sicilian ports supplies were to be transferred to ships for the short and protected run across the Strait of Sicily. But the advantages of this route were denied the Axis by the efforts of American bombers which, operating at short range, were much more effective against the Sicilian ports than they were against Naples. On March 22 American bombs ignited an explosion in the harbor of Palermo that devastated nearly thirty acres of docks and sank four merchant ships. In February, the bombers succeeded in forcing convoys to stage from Naples rather than from Sicily, tripling the distance they had to sail for Tunisia and thereby canceling the advantage of the Tunisian route over that of the Libyan. North of Sicily, moreover, convoys, unprotected by minefields, became liable to attack by British ships and submarines from Gibraltar.

Even the minefields of the Strait of Sicily ultimately redounded to the disadvantage of their creators. Their success in protecting shipping from surface attack was bought at the price of severe channelization of the convoy routes. The success of the British in laying minefields within those of the Axis worsened the channelization and resulted in a truly nightmarish problem of navigation for Italian seamen. Along the route of less than ninety miles from the western end of Sicily to Cape Bon the passage for convoys was nowhere more than three miles wide; for forty miles it was no more than one mile in width, and at some points less than half a mile wide. Within this narrow corridor the ability of vessels to manuever was constrained, and their vulnerability to aerial attack correspondingly increased.

The marginally adequate and severely channelized logistical system of the Axis gravely jeoparidized the supply of Heeresgruppe Afrika. But the final seal of doom for the enterprise was an Allied advantage that came to light only after the passage of more than three decades. The British, with some initial help from the Poles and the French, had succeeded in breaking many of the Germans’ most important ciphers. The information from this source, known as ULTRA, gave the Allies information about the Axis’ convoys that the official history of British intelligence in the Second World War describes as “virtually complete.” Daily digests disseminated to Allied air planners and naval commanders made known all points of origin, destinations, and schedules, and ships known to be carrying supplies of particular importance for Heeresgruppe Afrika could even be targeted specifically. The greatest secrecy shrouded the whole operation; targets, however tempting, were never attacked unless some other source duplicated the information, lest ULTRA be compromised.  Despite such precautions, the Germans at length realized the Al lies had very precise information about convoy movements, but drew the wrong conclusion about its source. Far from thinking their codes broken, they attributed the Allied information to disaffection in the ranks of their Italian allies.

Interdiction WWII Part IV - Northwest Africa November 1942-May 1943

Organization problems compounded the Allies’ material disadvantages. American air doctrine had been evolving in the same direction as that of the British. Field Manual FM 31-35, Aviation in Support of Ground Forces (April 9, 1942), provided that in each theater of war there should be an air support command to assist the ground forces. Each air support command was to be led by an airman, but this officer had markedly less independence than his British counterpart. There was no indication that he was to be equal in rank to the ground commander. More important, FM 31-35 stipulated that “the most important target at a particular time will usually be that target which constitutes the most serious threat to operations of the supported ground force. The final decision as to priority of target rests with the commander of the supported unit.” This disturbed airmen because FM 3 1-35 also provided that “aviation units may be attached to subordinate ground units.” The flyers were not mollified by the injunction that such attachments should be “exceptional and . . . resorted to only when circumstances are such that the air support commander cannot effectively control the combat aviation assigned to the air support command.” They feared that in practice the army would seize upon this provision to parcel out air power among units of the ground forces. Their apprehensions were soon realized. Not long before the landing in Northwest Africa, Eisenhower-who had not created a joint command for the British and American air units assigned to TORCH-ruled that the commanders of the major task forces should have control of the aircraft assigned to support them.

Eisenhower’s decision had seemed reasonable since many Allied components would be operating at a considerable distance from the general headquarters. General Anderson, dismayed by the effect of German dive bombers on his untried troops, availed himself of the prerogative it afforded him during his drive on Tunis. He demanded and received a group of fighters from the RAF for employment as a constant “air umbrella” over his army. The airmen, led by Air Chief Marshal Sir Arthur W. Tedder, the senior officer of the RAF in the theater, argued that this dispersion of aircraft was the worst of choices in the face of a superior Luftwaffe. Rather, they argued, the Allies should group their airplanes under a single commander so that at least local air superiority could be achieved for critical tasks. The Allies were further plagued by problems of coordination between the ground and the air forces. The much respected Allied naval commander in the Mediterranean, Admiral Sir Andrew B. Cunningham, signaled in despair to London that the organization of the air forces in Tunisia was completely chaotic.

Tedder, who tirelessly urged Eisenhower to create a unified command for the air forces, at length prevailed upon the supreme commander to appoint one of the most experienced of American airmen, Maj. Gen. Carl A. Spaatz, as his Deputy Commander in Chief for Air. Although Spaatz’s position, which he assumed on December 5, 1942, was essentially advisory, he soon managed to impose on the Tunisian air forces a division of labor loosely patterned after the organization the British had employed so well in the Egyptian desert. Spaatz made the British Eastern Air Command primarily responsible for support of the ground forces, and he employed the medium and heavy bombers of the American Twelfth Air Force chiefly against airfields and ports.

Spaatz’s appointment was the first in a series of steps that led to a total restructuring of the Allied air forces in Northwest Africa. On December 31 Eisenhower proposed that all the air forces in Northwest Africa be grouped under a new organization called the Allied Air Force, with Spaatz in command. The British not surprisingly assented to what was essentially their own proposal. They did, however, recommend that Eisenhower go one step further and group units by function regardless of nationality. Eisenhower stated his general agreement with this recommendation, but for the present thought it wise to preserve the separate identities of the Twelfth Air Force and the Eastern Air Command within the newly formed command structure.

The Allied Air Force was activated on January 5, 1943. Several days later (January 14-24, 1943), Roosevelt and Churchill, each with his military staff, met at Casablanca. The conference was on several scores a triumph for the British. It was agreed, as they had proposed, that North Africa should be used as the staging area for offensive action against Sicily. Casablanca also marked the final acceptance of British organizational principles, for the conferees prescribed a general structure of command for the Mediterranean theater that replicated the tried-and-tested British system. General Sir Harold Alexander was to become Eisenhower’s Deputy Commander in Chief with responsibility for the ground forces. Tedder, as chief of the Mediterranean Air Command, was to become air commander for the entire Mediterranean theater, while Spaatz, working closely with Alexander, would command in Northwest Africa an air force thoroughly integrated along the functional lines suggested by the British in December. When this unified force, the Northwest African Air Forces, became operational on February 23, 1943, it comprised three major commands: the Strategic Air Force, the Tactical Air Force, and the Coastal Air Force. The principal missions of the Strategic Air Force were destruction of the Axis’ ports and airfields. The Tactical Air Force was to be led by Tedder’s co-architect of aerial victory in the eastern desert, Air Vice Marshal Sir Arthur Coningham. Coningham’s responsibilities were air superiority and close air support. The tasks of the Coastal Air Force were to protect Allied shipping and destroy that of the Axis. The Coastal Air Force, drawn almost entirely from units of the Royal Air Force, had few aircraft suitable for the latter purpose. Two squadrons of American B-26 Marauders were therefore attached to it from the Strategic Air Force for the antishipping mission. The Strategic Air Force also provided P-38 Lightning fighters to escort the B-26s.

The Allies’ troubles of December and January, while serious, were nothing that could not be overcome with better weather and an intelligent application of the lessons of experience. The Axis faced only a single major problem, but it proved intractable and in time led to disaster: Its position in Tunisia was logistically untenable. The Germans, the primary instigators of the fatal commitment in Northwest Africa, had made too many optimistic assumptions about the availability of shipping in the Mediterranean. They had, in particular, counted too much on vessels they planned to seize from France The burden of transporting supplies to Tunisia therefore fell upon Italy, for Germany’s merchant fleet was blockaded in the North Sea.

When Italy surrendered in September 1943 there remained to her 272 merchantmen with a burden of 500 tons or more-in all, 748,578 tons of shipping. A fleet of this size would have sufficed to supply Tunisia had it not been for the Axis’ strategic overextension and a shortage of vessels suitable for the dangerous run to Tunisia. Only speedy ships were suitable, and by 1943 they were scarce. Too many had been lost on the Libyan route. The ships also had to be small-to make them difficult targets for aircraft and to minimize the effect of losses. But small vessels, too, were lacking by 1943. In February 1943 the Axis had, even with recent seizures from France, only about 300,000 tons of shipping suitable for the run to Tunisia, and by no means all of it was available for that purpose. About half of the remaining ships were damaged, and the Allies systematically bombed Italian shipyards to slow repairs. The Axis, moreover, also had to sustain the garrisons and considerable populations of Sicily, Corsica, Sardinia, and the Dodecanese Islands. Sicily alone required 200,000 tons of coal each month. Of this amount, the inadequate railroads of southern Italy could move but a fifth to the Strait of Messina for transshipment by ferry or lighter. The combined effect of all the foregoing was that at no time between January and May 1943 were more than 30,000 to 50,000 tons of shipping available to supply North Africa. There was yet another problem in the Italian Navy’s shortage of destroyers. Convoys laden with critical supplies were often delayed because there were no unengaged warships to escort them.

The German commanders in Tunisia were on the horns of a dilemma that admitted of no solution: Their logistical support was inadequate, yet the only appropriate strategy required a prodigal expenditure of supplies. Von Arnim, who had been predicting disaster since January, outlined the predicament in an appreciation of February 26, 1943, which Rommel seconded shortly thereafter. Von Arnim estimated that Heeresgruppe Afrika was responsible for the maintenance of 120,000 soldiers and 230,000 civilians. The quartermaster of the Heeresgruppe put its average monthly consumption of supplies at 69,000 tons. The chief transportation officer of the Commando Supremo had estimated early in February that he could send only 70,000 to 82,000 tons of supplies monthly to Tunisia. Since the convoys would be subject to an anticipated loss rate of 25 percent, meeting even minimum requirements of the Heeresgruppe was highly improbable. Matters were even worse than these figures implied. Superior Allied armies were converging on Tunisia. Little prospect existed that the forces of the Axis, hemmed in on the shore of northeastern Tunisia, could long withstand the Allies’ concerted assault. Defeat of the Allied armies in detail before they could mass was therefore imperative. At least one enemy army, von Arnim argued, had to be put “out of action for six months. . . . All other victories would change nothing, but only postpone the inevitable.” But an active defense, with a heavy employment of armored forces, would entail a much greater than normal expenditure of supplies. To implement this strategy, and to allow for inevitable disruptions of supply by enemy action and weather, the Heeresgruppe would have to receive not less than 140,000 tons monthly. Only then, von Arnim concluded, would a successful defense against the impending general offensive of the Allies be possible. As yet, Tunis was “a fortress . . . without reserves of ammunition or food.” Were he in Eisenhower’s place, he observed, “I would not attack, but with every means attack convoys and harbors while battering the Luftwuffe.” With a complete disruption of supply, Tunis must fall by July 1.

Interdiction WWII Part III - Northwest Africa November 1942-May 1943

Lt. Gen. Sir Bernard Law Montgomery, since August the commander of the Eighth Army, had driven the Germans into headlong retreat at the second battle of El Alamein in October. Rommel soon after concluded that it would be impossible for the Axis to hold North Africa. German submarines had lost the Battle of the Atlantic, he argued, and the Anglo-Americans would in time muster in Africa a force too large to be resisted. He urged that his army consolidate with Nehring’s and launch an offensive to beat back the Allies long enough to permit the evacuation of the German forces from Africa for the defense of Europe.10 But Hitler was adamant that an invasion of southern Europe should be staved off as long as possible by a stand in North Africa even, as he seems eventually to have concluded, at the cost of the forces sent there.” Kesselring, ever inclined to optimism, believed that indefinite resistance would be possible in mountainous Tunisia where the Allies would have to operate at the end of a long overland line of supply. He shared Rommel’s opinion that logistics would be decisive, stating on November 24 that “in the last analysis everything depends upon supply.” But he differed from the general in his conclusion that the “air and sea situations” were “not unfavorable,” as the convoy routes from Italy to Tunisia were shorter and easier to protect than those to Libya.

Having secured Algiers, General Anderson set out for Tunis on November 11. Nearly 400 miles of mountainous terrain separated Algiers from Tunis. An advance wholly overland would therefore have been too slow, as the campaign had become a race against the German airlift from Italy. On November 11 TORCH’S reserve force landed at Bougie, 100 miles east of Algiers. The loss of three of the four transports involved in this operation to German aircraft after they had disembarked their troops confirmed the wisdom of the decision to make the initial landings farther west. Bône fell to British paratroopers on November 12. An American airborne force took Gafsa three days later, as the larger part of Anderson’s task force struggled overland by road and rail. By November 16, advance parties reached the Tunisian frontier. Only small skirmishes had so far occurred between the Anglo-Americans and small German and Italian patrols.

Anderson began his general offensive on November 24. In the face of intensifying German resistance, the Allied forces captured Djedeida on November 28. A mere twelve miles from Tunis, Djedeida marked the farthest Allied advance of the winter campaign, for Nehring recaptured it on December 1. Stymied by German resistance and rains that made roads and airfields unusable, Eisenhower halted the advance. He consolidated his forces along a line that ran from Medjez-el-Bab in the north through Ousseltia and Faid south to Gafsa.

The Allies had lost the race for Tunis. Part of the price they would pay was the presence of Rommel and his First Italian Army (the former Afrika Korps) in Tunisia. Rommel’s plan for a concentration of forces in Tunisia had not been initially well received by his superiors, who insisted that he make a stand in western Libya. This decision, however, was reversed in December. The Germans had earlier decided upon a series of local offensives to enlarge their constricted Tunisian bridgehead. For this reason, Nehring was replaced on December 9 by an experienced commander of armor withdrawn from Russia, Maj. Gen. Jurgen von Arnim. But when the reserves to support the offensive strategy were diverted to meet a developing crisis on the Russian front, reinforcement of von Arnim’s force by Rommel’s became necessary if there was to be an active defense of Tunisia. When the First Italian Army reached Tunisia it joined with the Fifth Panzerarmee to form Heeresgruppe Afrika which Rommel commanded.

When the Germans later reflected upon their defeat in Tunisia, it seemed to them that the Allies had come only “gradually” to realize that “supplies were the weak link of the Axis position in Tunisia.” This perception may seem strange, given the success with which the Royal Navy had for so long attacked convoys bound for Libya. But the progressive consolidation of the Axis’ forces in Tunisia spelled a respite for the Axis’ convoys by reducing the scope of Allied naval action. The Italians had heavily mined the Strait of Sicily. Convoys for Tunis, which staged from Sicily, were relatively safe from naval attack as long as they remained within the channels left within the minefields.  

The manifold problems of the Allied air forces also delayed effective attacks on the convoy routes from Sicily. Not until February 1943 were they ready to begin antishipping operations on a large scale. The Desert Air Force of the British Eighth Army was for much of January and February beyond range of the Strait of Sicily. The Germans, moreover, had so methodically plowed and mined the airfields of western Libya that the Desert Air Force was slow to start operations even when it was within range of the convoy routes. It became fully operational in Tunisia only around March 1. The situation of the Allied air forces already in Tunisia and eastern Algeria-the American Twelfth Air Force and the Royal Air Force’s (RAF’s) Eastern Air Command-was more serious still. Throughout December and January they had to contend with a potent Luftwaffe and intractable problems with basing, training, supply, and organization. The Germans began 1943 with slightly more aircraft in Tunisia than the Allies. January 1 saw 690 German combat aircraft in Tunisia or within range of it; the Allies had 480. While the Allied air forces had larger establishments of aircraft in the theater, they were unable to bring their full strength to bear because of the poor quality of their advanced airfields and the logistical disruptions caused by their rapid advance. In early December, the Allies had only three forward fields for their fighters: Bane, Youks-les-Bains, and Souk-el-Arba. These were, respectively, 120, 150, and 70 miles from the front. The latter two were nearly unusable during the heavy rains of the North African winter. This defect was not easily remedied-the American engineers responsible for the fields had not received their heavy equipment, and the portion of Tunisia held by the Allies was hilly and afforded few alternative sites.

Bases were also a problem for the Allies’ bombers. Not until late December did the opening of airfields near Constantine, Algeria, put the Strait of Sicily within range of medium bombers. Logistical difficulties impeded the functioning of these bases once established, and only in February were operations at all efficient, although medium bombers had begun antishipping operations on a small scale in early January. B-17s had begun to attack the ports of Tunis, Bizerte, Sousse, and Gabes early in December. But distance was a limiting factor even for these long-range aircraft: They had to operate from an inadequate field near Oran, 630 miles from Tunis-farther than London was from Berlin. A move to a better field at Biskra in western Algeria in late December increased the sortie rate of the heavy bombers somewhat. But maintenance and repair remained so inadequate for all components of the Allied air forces that in his. report of December 4 Eisenhower quoted his airmen to the effect that “near or complete breakdown” would ensue within two to seven days unless operations were curtailed. The inexperience of the Twelfth Air Force exacerbated all these problems. On December 21 the Twelfth’s commander, Maj . Gen. James Doolittle, estimated that fully 75 percent of his men were untrained or only partially trained. At this time the Allies could on any day operate only about a third of the aircraft they had in Northwest Africa.

The position of the Germans with respect to bases was much more fortunate. Besides their airdromes in Sicily and Sardinia, they had at Sidi Ahmed, El Aouina, Sfax, Sousse, and Gabes well-constructed fields, which, in contrast to the muddy tracts of the Allies, were usable throughout the rainy North African winter. These bases were the chief reason for the Luftwuffe’s air superiority: It could station more fighters within range of the Tunisian battlefield than the Allies. The Axis also controlled the well-drained coastal plains, large portions of which were usable without preparation as landing fields. This was a particular advantage for close air support as long as the Luftwuffe had air superiority. Because the Germans could station dive bombers close to the front lines, their ground commanders could quickly receive support from these aircraft, which had little to fear from the distantly based fighters of the Allies. Eisenhower reported on December 4 that air support for his forces had been “insufficient to keep down the hostile strafing and dive-bombing” that had been “largely responsible for breaking up all attempted advances by ground forces.”