Adrienne LaFrance at The Atlantic:
Starting late in the evening on June 2, 1919, in a series of coordinated attacks, anarchists simultaneously detonated massive bombs in eight American cities. In Washington, an explosion at the home of Attorney General A. Mitchell Palmer blasted out the front windows and tore framed photos off the walls. Palmer, in his pajamas, had been reading by his second-story window. He happened to step away minutes before the bomb went off, a decision that authorities believed kept him alive. (His neighbors, the assistant secretary of the Navy and his wife, Franklin and Eleanor Roosevelt, had just gotten home from an evening out when the explosion also shattered their windows. Franklin ran over to Palmer’s house to check on him.) The following year, a horse-drawn carriage drew up to the pink-marble entrance of the J. P. Morgan building on Wall Street and exploded, killing more than 30 people and injuring hundreds more.
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The spectacular violence of 1919 and 1920 proved a catalyst. A concerted nationwide hunt for anarchists began. This work, which culminated in what came to be known as the Palmer Raids, entailed direct violations of the Constitution. In late 1919 and early 1920, a series of raids—carried out in more than 30 American cities—led to the warrantless arrests of 10,000 suspected radicals, mostly Italian and Jewish immigrants. Attorney General Palmer’s dragnet ensnared many innocent people and has become a symbol of the damage that overzealous law enforcement can cause. Hundreds of people were ultimately deported. Some had fallen afoul of a harsh new federal immigration law that broadly targeted anarchists. One of them was Luigi Galleani. “The law was kind of designed for him,” Beverly Gage, a historian and the author of The Day Wall Street Exploded, told me.The violence did not stop immediately after the Palmer Raids—in an irony that frustrated authorities, Galleani’s deportation made it impossible for them to charge him in the Wall Street bombing, which they believed he planned, because it occurred after he’d left the country. Nevertheless, sweeping action by law enforcement helped put an end to a generation of anarchist attacks.
That is the most important lesson from the anarchist period: Holding perpetrators accountable is crucial. The Palmer Raids are remembered, rightly, as a ham-handed application of police-state tactics. Government actions can turn killers into martyrs. More important, aggressive policing and surveillance can undermine the very democracy they are meant to protect; state violence against citizens only validates a distrust of law enforcement.
But deterrence conducted within the law can work. Unlike anti-war protesters or labor organizers, violent extremists don’t have an agenda that invites negotiation. “Today’s threats of violence can be inspired by a wide range of ideologies that themselves morph and shift over time,” Deputy Homeland Security Adviser Josh Geltzer told me. Now as in the early 20th century, countering extremism through ordinary debate or persuasion, or through concession, is a fool’s errand. Extremists may not even know what they believe, or hope for. “One of the things I increasingly keep wondering about is—what is the endgame?” Mary McCord, a former assistant U.S. attorney and national-security official, told me. “Do you want democratic government? Do you want authoritarianism? Nobody talks about that. Take back our country . Okay, so you get it back. Then what do you do?”