From the Greek word anarchos, meaning without government or authority, anarchism is the belief that governmental regulation is both unnecessary and harmful to society. Human beings are by nature good, but are corrupted by societal institutions. Those institutions, particularly the state, must be destroyed to allow the natural development of voluntary associations among individuals and groups. Forms of anarchism existed in ancient times and among some early Christian sects. The movement became associated with violence under the influence of the Russian revolutionary Mikhail Bakunin (1814-1876), who eventually lost out in an ideological struggle with Karl Marx. A wave of political assassinations in Europe during the 19th and early 20th centuries was a means employed by anarchists to destroy corrupt governments. Anarchism has never been a major force in the United States, but did have an early advocate in the utopian Josiah Warren (1798-1874). The movement lost what meager support it had in the wake of the Haymarket Riot and the McKinley assassination. In 1901, Congress enacted legislation barring known anarchists from entering the United States. Such notable activists as Emma Goldman and Alexander Berkman were deported at this time. Post-World War I xenophobia was evidenced in the trial and execution of anarchists Sacco and Vanzetti in the 1920s. The movement has few adherents today and is largely confined to making protest statements at well publicized international gatherings.