An accurate history from Front Page Mag: Mussolini the socialist

The pragmatist
Although Mussolini never ceased preaching socialism in some form, his actions when in power were like those of most politicians: Many unrealistic promises were broken and policies were adopted that in fact hurt the workers (such as wage cuts). The important point, however, is that the policies he in fact adopted once in power were not adopted for mere ideological reasons but because they were the policies that he thought would work best for Italy and, thus, ultimately for all Italians. As "Conservative" political parties tend to think in this way also (Gilmour, 1978), it is presumably in part this that causes Mussolini to be referred to as a Rightist. His appeal to Italians, however was as a socialist and a nationalist.

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Front Page Magazine: "Left-wing Fascism: An Intellectual Disorder"