Between 1983 and 1985, May 19th members carried out a string of night-time bombings of government and military targets in Washington and New York under the names Armed Resistance Unit and Red Guerrilla Resistance — including the National War College, the Washington Navy Yard, and, on November 7, 1983, the U.S. Capitol itself, where a device outside the Senate chamber answered the invasion of Grenada. The actions were carried out with warning calls and caused no injuries, only property damage.
The Capitol bombing nonetheless produced a permanent transformation of the building's security and stands as the charge around which the government built the Resistance Conspiracy case. For the organization it was the continuation of Weather-style armed propaganda; for prosecutors it was terrorism at the heart of the state, and it guaranteed that May 19th's prisoners would receive some of the longest political sentences of the era.