Leftist criticisms of radical segmentation theory were several. On theoretical grounds, it was argued that segmentation theory was overly dependent upon ad hoc explanations and lacked theoretical clarity. Even results from empirical studies were contradictory, indicating that overall patterns of working class division and segmentation were broadly diffused, tending to transcend neatly compartmentalized boundaries. This was true not only for the United States, but especially in Europe where significant numbers of immigrants gained entrance into primary labor markets in Germany, France, and Italy instead of entering the secondary markets as segmentation theory would have expected. Moreover, when it came to the historical development of dual economic structures, more attention was paid to capitalist' s motivations than to those of workers, especially unionized ones.
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