The McNamara brothers bombed the Los Angeles Times building in 1910, killing 21 people. They opposed the newspaper owner's conservative views against unions. A third bomb was found and traced back to the brothers, who were sentenced to prison. Tensions had grown due to unsafe working conditions and employers not recognizing unions. The bombing led to investigations into industrial relations and new laws protecting workers' rights. However, current efforts reducing collective bargaining could lead to new acts of domestic terrorism if workers' frustrations are not addressed through legal protest.