Italy's entry into WWII (June 1940) and its North African campaign were driven by Fascist imperial ideology, strategic geography, and a miscalculation of British weakness.
Libya (colonized 1911–1932) was directly accessible from Italy (Sicily → Tripoli: ~300 km). Troop/supply convoys could run under land-based air cover — unlike East Africa or the Balkans.
Control of North Africa meant:
Mussolini sought to restore the Roman Empire — Mare Nostrum ("Our Sea"). North Africa was the natural southern shore of this imperial lake. Libya was already Italian; Egypt, Tunisia, Algeria were the next prizes.
Britain (Egypt, Suez, Cyprus, Malta) and France (Tunisia, Algeria, Morocco) dominated the Mediterranean. Italy, a late-unified Great Power, demanded its "place in the sun." North Africa was the theater to displace them.
North Africa was the only theater where Italy could act independently (initially).
After Dunkirk (June 1940), Britain stood alone, reeling. Italy believed Britain would negotiate or collapse in the Mediterranean. Mussolini launched Operazione E (invasion of Egypt, Sept 1940) expecting a walkover. Instead, Operation Compass (Dec 1940) destroyed the Italian 10th Army.
Italy's North African gamble failed catastrophically. It required massive German intervention (Rommel's Afrika Korps, 1941) and ended with total Axis surrender in Tunisia (May 1943) — 250,000+ POWs. The "Roman Lake" became the launchpad for the Allied invasion of Europe.