WI: Mussolini joined WW2 straight away in September '39?

Simple question: what if Mussolini joined WW2 straight away in September '39? According to a biography of Mussolini that I read Egypt was practically undefended at the time and even the incompetent Italian army should have been able to make serious inroads, especially given British commitments elsewhere in Europe. Similarly, Malta was barely defended at the time and the Italians should have been able to take it, even without German assistance IMHO. So what if the Italians joined WW2 immediately in September 1939.
 
Simple question: what if Mussolini joined WW2 straight away in September '39? According to a biography of Mussolini that I read Egypt was practically undefended at the time and even the incompetent Italian army should have been able to make serious inroads, especially given British commitments elsewhere in Europe. Similarly, Malta was barely defended at the time and the Italians should have been able to take it, even without German assistance IMHO. So what if the Italians joined WW2 immediately in September 1939.
Do not think it would have mattered cause the axis ability to produce supplies and goods for the allies was always gonna surpass anything the axis could prkoduce.if anything it would just have killed more people on both sides.
 
In September 1939 the French Armee d'Afrique was quite large. Over 50 regiments of Zouaves, Tirailleurs, and Foreign Legionnaires. Many were recalled reservists, but still constituted a considerable force with artillery and light armored vehicles on the Western border of Libya. French forces in southern Tunisia were less than 100 miles from the main Italian port of Tripoli. The Italian Army couldn't just begin an invasion of Egypt without considering what might happen on the other side of Libya. They would have to keep major forces in the West to keep the Armee d'Afrique out of western Libya and Tripoli.
 
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