On 13 September 1940, the Italian X Army advanced out of Libya and into Egypt to seize Cairo and the Suez Canal, in the first scene of the first act of what would become known over the next three years as the Western Desert Campaign. The Western Desert, known so by the British because it was west of the Middle East, was a 150 mile wide and 1000 mile long strip of rocky desert in North Africa between Tripoli in Libya and Mersa Matruh in Egypt. It was bordered by the Mediterranean Coast to the north, and impassable terrain to the south: the salt flats of the Qattara Depression and giant dunes of the Sahara. The Western Desert had but a single coastal road, the Via Balbia, although there were some Bedouin tracks that connected the oases further south.
With the French threat from Tunisia neutralized by her surrender, the Italian X Army attacked east along the Via Balbia into Egypt. They were met by units of the British Armoured Division (soon to be renamed the 7th Armoured Division, aka The Desert Rats), the New Zealand Division led by the indestructible MajGen Bernard Freyberg, and the “Red Eagles” of the 4th Indian Division. But before those units became famous later in the war, in September 1940, they were underequipped, undermanned, and under trained composite formations only thrown together when the Italians declared war in June. They were overwhelmed by the Italians while defending the frontier. Yet the British and Commonwealth troops conducted a skillful delaying action and scorched earth policy, principally by destroying the coastal road, which exacerbated the Italian supply problems.
The Italian supplies had to be shipped from Italy to Benghazi or Tobruk, or even worse farther west to Tripoli, and then driven to the frontier hundreds of miles east. It didn’t help that Italy was not even remotely prepared for Mussolini’s declaration of war. The Italian merchant marine was completely surprised, and a full 1/3 of all Italian shipping was captured within two days of the declaration, because they were caught in neutral or hostile ports. Furthermore, the rough terrain was hell on the vehicles, and the hot desert wind, called the Sirocco, coated everything in a fine machinery destroying dust. Soon spare parts were fighting with food, fuel, water and ammunition for the limited space in the ships and trucks. Italian trucks were using 60% of the fuel they carried just to get to the forward units. Upon learning that the Duke of Aosta in the Sudan was stopped by the same logistics problems, Field Marshal Graziani decided to halt the Italian offensive on 16 September when he reached Sidi Barrani, just 65 miles inside Egypt. There the Italians dug in to buildup supplies for the next push.
However, the Italians only learned the first half of the First Rule of the Western Desert: “Every step forward for the attacker was one step further away from their supplies”. They didn’t yet understand the second half, “Every step back for the defender was one step closer to theirs”.
The British did.