Final answer:
Historians criticise Giolitti's choice for supporting Mussolini's policies, which led to an inefficient government, a poorly equipped military, and long-term damage to Italy's stability and prosperity. Corruption and misleading leadership also contributed to the negative assessment of the Fascist regime.
Step-by-step explanation:
Historians now criticise Giolitti's choice because, while Mussolini's policies were initially perceived as a means for providing political stability and protecting against the spread of communism, in hindsight they led Italy into an era of totalitarianism and were detrimental to the nation's long-term interests. Mussolini's Fascist government was seen as inefficient and the military was poorly trained and equipped. This became evident during World War II. Additionally, corruption was rampant among Mussolini's circle of leaders, and they often misled him about the actual conditions of Italy. Furthermore, the suppression of opposition and jailing of political enemies, while initially providing an illusion of stability, ultimately did not prepare Italy to face the economic and social challenges effectively. Mussolini's decision to support Hitler in the invasion of the Soviet Union also led to massive Italian casualties.