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To a certain extent, this was the fault of the U.S.’s xenophobia, which alienated many Italians and made them desperate for acceptance.

Mussolini had been aware since the early 1930s that the only effective way to exploit Italian Americans for political purposes was to mobilize them as a lobby. He, therefore, encouraged them to become U.S. citizens so that they would be eligible for the suffrage and, as U.S. voters, could pressure American political institutions such as Congress and the Presidency into adopting policies that benefited Italy and Fascist interests.

This strategy reached a climax during the Italo‐Ethiopian War, when the “Little Italies” supported Mussolini’s war efforts and lobbied Congress to prevent the passing of a neutrality legislation that would have granted the U.S. president the power to impose economic sanctions on Italy.

[…]

Mussolini thought that Italian communities would be more useful if they turned into American electoral lobbies. In his view, Italian Americans could be loyal U.S. citizens providing that they maintained strong spiritual ties to their mother country, which involved promoting Italy’s interests in the United States.

In the Spring of 1932, Il Duce officially stated to German journalist Emil Ludwig: ‘We consider it a matter of principle to ask our fellow countrymen [Italian Americans] to be loyal to the State in which they live. If they acquire full citizenship in the spiritual sense as well as in the material, they count for something; but if they hold themselves aloof from their adoptive land, they remain helots. Since we began to advocate the policy of assimilation, many Italian‐born citizens have attained high positions over there.’

(Emphasis added.)