"The narrative of immigration as regeneration imagined the republican system itself, as well the economic arrangements on which that system rested, as a great hopper of assimilation with the capacity to transform the oppressed dregs of the Old World into patriotic republicans. The regeneration narrative evinced a certain optimistic, almost self-congratulatory confidence that the transformative power of geography and political institutions would preserve for all time the core republican values of personal independence and citizenly virtue. Notwithstanding the hopper's tremendous power, however, its machinery was also remarkably fragile. Its effectiveness depended entirely on the integrity of its various constituent parts: independent, virtuous citizenship rooted in individual economic proprietorship; the immersion of immigrants in social and political institutions that promoted the adoption of republican values; and finally, the moral and political natures of immigrants themselves. These were the essential conditions of the nation's liberal immigration and naturalization policy, and virtually from the beginning they appeared threatened by the same dangers that jeopardized virtuous republican citizenship generally: concentrations of population in great manufacturing centers; the clustering of immigrants into ethnic enclaves where, instead of assimilating, they allegedly formed distinct political identities and interests defined by their shared national origins; and finally, the emergence of a permanent class of "dependent" laborers."