Bombs have been around for centuries. The military units called “Grenadiers” in European armies used throwable black-powder bombs, early versions of what today are called grenades. They were heavy, so Grenadiers were tall, strong soldiers able to throw grenades for a distance. Terrorism has been around for many centuries, most infamously the period called the Terror (1793-94) in the French Revolution. However, the combination of bombs and terrorism is considerably more recent, dating to the 1870s and 1880s.

Black powder had been used occasionally for terrorism before the 1800s, with the most famous incident being the Guy Fawkes gunpowder plot to blow up the English Parliament in 1605. Fawkes used barrels of gunpowder rather than a bomb in the modern sense. Terrorism was nothing new in the United States, where, for example, tarring and feathering of Loyalists during the American Revolution was a terror technique designed to quell Tory sentiments. However, terrorists using bombs to accomplish political ends in the United States goes back only about 150 years. That’s partly a result of the rise of political movements seeing violence as legitimate, and partly the result of the development of dynamite.

In the United States, the first terrorist bombs, so far as is known, began to appear in the 1880s. Mines and booby traps had been used by Confederate agents in the Civil War, in attempts both to cause military damage, sabotage, and to panic civilian populations. Late in the war, Confederate agents operating out of Canada plotted arson in New York City, but their tools did not much resemble bombs, and failed anyway.

The emergence of the radical ideology of anarchism, brought to the United States originally by Italian and German immigrants, emphasized propaganda of the deed, which sometimes meant violence. The philosophy of anarchism was vaguely socialist, and the movement was fractured into many splinter groups. Some of the anarchists advocated violence, and the cartoon stereotype of the bomb-throwing anarchist has some basis in American history.

Other groups sometimes used bombs. There are allegations that around 1900, the Western Federation of Miners used bombs to sabotage mines during strikes. The members used explosives in mining, and those skills were easily transferred to making bombs. Several IWW members were accused of murder by bomb. Other unions are known to have used dynamite during strikes. A number of occupations used dynamite in their work, including miners, bridge builders, quarry workers, and road builders. Radicals or misfits could find ways to buy dynamite, or steal it.

Of the earliest attacks, the most notorious might be the Haymarket bombing in Chicago in 1886, which caused the deaths of police officers and led to the execution of men who may have been innocent. One result was that the campaign for the eight-hour day was set back for a generation. In 1910, terrorists blew up the Los Angeles Times with a heavy loss of life, and the attack involved the Ironworker’s Union, which had been using dynamite to intimidate non-union employers. Both incidents had extremely negative consequences for labor and unions. 

In 1936, Milwaukee was terrorized for a week by an apparently random spree of bombings that turned out to be the result of two alienated young men. And in New York City, a bomber managed to commit a series of bombings that spanned 15 years, 1940-1955, with so many in his last couple of years that the press christened him the “Mad Bomber,” making New Yorkers afraid of going to places like the Port Authority Bus Terminal and the Radio City Music Hall.