In the sunshine of Casablanca, the Joint Chiefs, with Roosevelt and Churchill as the great overseers, thrashed out a way forward. In the end, the Americans agreed on a joint assault on Sicily in part because a great Allied force had already been amassed in North Africa and in part because of the shipping issue. As the American chiefs accepted, shipping was the biggest obstacle to their favoured strategy of a cross-Channel invasion of Nazi-occupied France. The drain on supplies caused by the fighting in North Africa had been startling. Both Britain’s and America’s war effort had suddenly and massively increased, which meant shipping was in considerably greater demand. After all, it wasn’t just the growing scale of operations in the Mediterranean, nor even the ongoing build-up in Britain, that had to be supported; there was also the war in the Pacific and in the Far East being prosecuted in parallel.
As things stood, the eastern Mediterranean remained closed, which meant shipping to the Far East was still heading all the way around South Africa, a long route which in turn caused a further drain on this precious resource. Capturing Sicily would open up the Mediterranean, enabling Allied shipping to use the Suez Canal and so save considerable time and effort. In other words, the British argued, by invading and taking Sicily, the Allies would be moving closer to making the cross-Channel invasion possible. In any case, argued General Sir Alan Brooke, the British CIGS, it was doubtful Germany could be sufficiently weakened to allow a successful cross-Channel invasion that year. The Dieppe Raid of August 1942, in which half the attacking force had been lost, had been a disaster and a salutary lesson. Yet the Soviet Union still needed diversionary support. Reluctantly, the American chiefs accepted that a cross-Channel operation in 1943 was not practicable; yet the political and military pressure to continue ground operations that year following the end of the North African campaign, not least to relieve pressure on the Soviet Union, was immense. Taking Sicily would help in forcing the Germans to spread their weakening resources still further, especially if, as hoped, the Italians were knocked out of the war. General Marshall and the US chiefs conceded there should be ongoing operations in the Mediterranean – but only on the non-negotiable condition that the British back a cross-Channel invasion of Nazi-occupied France in 1944.
And so it was settled, on 23 January 1943, with a directive issued to Eisenhower. Although Sardinia had been discussed, Sicily was the only realistic target. It was a far greater political and military prize, but also considerably more manageable now that Malta had been transformed from the most bombed place on Earth into what was in effect a stationary aircraft carrier just 60 miles south of Sicily. Everybody accepted there could be no invasion without fighter cover, which ruled out southern Greece and, realistically, Sardinia too.
Agreeing that Sicily should be the next focus was, however, the easy part. Eisenhower had announced his three service chiefs on 11 February – Alexander as land commander, Air Chief Marshal Sir Arthur Tedder as air commander and Admiral Sir Andrew Browne Cunningham as naval commander. In terms of experience and seniority it made perfect sense for them to all be British – but just three days later had come Rommel’s strike against the Americans at Sidi Bou Zid that opened the way for the defeat at Kasserine. Suddenly Alexander was being diverted to take charge of the crisis in Tunisia, and clearly this was his first priority, demanding that he devote much of his time, and his mental and physical energy, to touring the front and making the necessary dispositions.
None the less, by this stage Alexander had already concluded that the secret to the Allied way of war was to draw together more closely than ever before the three elements in which it was conducted: land, air and water. ‘Army, Air Force and Navy must become a brotherhood,’ he said.1 This mantra held especially true for HUSKY and was the starting point for planning for the invasion. From the outset, it was agreed that two invasion forces would be needed for HUSKY, one British and one American, and these, for the time being, were allotted code numbers. Force 545 was to be British, commanded by General Montgomery, and would sail for Sicily from Egypt. For planning purposes, Force 545 was based in Cairo, 1,400 miles away, even though Montgomery was still commanding Eighth Army in Tunisia. The American Force 343 was to be commanded by General Patton, known as a firebrand and an armour expert, and currently based in Algeria. Its headquarters was at Rabat in Morocco, over 1,000 miles from Tunis – but soon Patton, too, was pulled into the Tunisian battle to take command of II Corps after the sacking of the hopeless General Lloyd Fredendall. The air commanders also had their hands full with the Tunisian battle, leaving only the Allied navies with any kind of time to plan, although even they were caught up in anti-shipping operations against Axis convoys. Absentee landlordism was to be a major feature of the planning of HUSKY, but part of the reason for agreeing to Sicily was that most of the forces – including their commanders – were already in the Mediterranean theatre. Bringing in a new and untested team would rather defeat the point of the object. Even so, and to make matters more complicated, there was a planning team in London and also ostensibly another under Alexander in Bouzarea, near Algiers: Force 141, so named for security reasons but also after the main room used in the St George Hotel in which the team were housed.
There were at least certain prerequisites on which everyone was agreed. Air superiority was essential, so too was naval superiority, and so too was a sufficient speed with which ground forces could be landed and reinforced compared with the likely rate of Axis reinforcement. Naval superiority was more or less a given, since the Italian fleet had not been to sea since the middle of the previous year, but air superiority was not yet assured and there was a huge question mark over how effectively the Allies could build up their strength once ashore.
The geography of Sicily hardly helped. Messina was the ultimate goal, as the city closest to the toe of the Italian mainland and the access point through which enemy supplies would principally flow. It was also comfortably the largest port on the island, with a daily handling capacity of some 4,500 tons. However, it was in the north-eastern corner of the island, which was dominated by the mighty volcanic mass of Mount Etna. ‘It was strongly defended,’ noted Alexander, ‘difficult of access and well out of range of air cover.’2 As an invasion point, it was a non-starter. Away to the west along the northern coast was the second largest port, Palermo, with a daily capacity of 2,500 tons; but near to Palermo was the Trapani–Castelvetrano complex of airfields. Along the central eastern coast, some 150 miles from Trapani, was Catania, the third largest port, and south of that, Augusta and Syracuse. Catania had an airfield, and a little further inland was the Gerbini airfield complex, while on the southern coast there were further airfields at Gela and Comiso. When planning began, there were nineteen airfields on Sicily – no small number – but by the end of June there were thirty.
Planners reckoned they needed to be unloading some 3,000 tons of supplies a day initially, rising rapidly to 6,000 as the invasion strength grew. Operation TORCH, although a major amphibious landing, wasn’t a huge amount of help in terms of lesson learning because the Vichy French had had no air forces, the enemy strength had been known and the ports had been swiftly captured. For HUSKY, hastily developed landing craft could deliver a certain amount of supplies directly on to beaches, but this was considered a temporary measure at best. The swift capture of ports was recognized to be essential.
Yet in this respect the island was poorly served, despite its long history as a maritime base. Shipping had grown massively in recent decades and so had armies, yet Sicily, still centuries behind the times in many ways, had not caught up. Without Messina, it was estimated the east coast ports could manage around 3,400 tons a day, while western harbours – Palermo plus Trapani and a couple of other