When President William McKinley was assassinated in 1901 by an American anarchist with a foreign-sounding name, a new wave of xenophobia was unleashed. Calls to exclude anarchists from immigrating intensified, and Theodore Roosevelt's first Congressional address urged the exclusion of aliens who even espoused anarchist beliefs. At least nine anti-anarchist bills were introduced in the first session of the 57th Congress, and several Constitutional amendments were proposed that would have permitted the suppression of anarchism. The effort came to fruition in the Immigration Act of 1903, the first act barring immigration solely on the basis of political belief.