Tresca became a prominent figure among Italian-Americans for his opposition to fascism and was reported to Benito Mussolini as a leading enemy of the fascist movement. Tresca edited an anti-fascist newspaper named "Il Martello", where he attacked the myths that undergirded Mussolini's power. Tresca was monitored by the United States Department of Justice, who sought to deport him, and by Rome, where Mussolini feared that Italian-Americans would hurt his reputation with the United States and its banks. With pressure from the Italian ambassador to ban Tresca's newspaper, the American government charged Tresca with publishing obscenities. Tresca was sentenced and subject to deportation, but public dissent led the United States President Calvin Coolidge to commute Tresca's sentence. The fascists turned to violence, with a bombing assassination attempt in 1926, after which the antifascists fought back. Tresca contributed towards stopping Mussolini's ideological spread among Italian-Americans, despite Tresca's lack of reach into Italian-American media and business influence.