The Poway shooter used an age old terrorist tactic. The media fell for it.

On Saturday, a 19-year-old student allegedly walked into a synagogue in Poway, Calif., armed with a semiautomatic rifle and opened fire on the congregation that was commemorating the last day of Passover, killing a 60-year-old woman and injuring three others.

In 2016, another 19-year-old walked into a church in Normandy, France, slitting the throat of an 84-year-old French priest, Jacques Hamel, and injuring another.

These two attacks took place nearly three years and more than 5,000 miles apart. Yet they represent a common feature of political violence in the 21st century: not only did the perpetrators attack the faithful in their houses of worship, they were also acting in the name of global, virulent ideologies that both, paradoxically, emerged in response to globalization.

The first young man appears to have been inspired to violence by white nationalism, the second by ISIS. They took it upon themselves to murder in the name of a greater cause, aiming to use symbolic violence to generate mass media attention that could inspire sympathizers and intimidate targeted groups. Such acts have a long history, and the best way to combat them is to deprive these terrorists of the attention they crave and use the very same media channels they aim to manipulate to fight back.

These sorts of terrorist attacks fall under the umbrella of “propaganda of the deed,” a category that dates to the anarchist violence of the late 19th and early 20th centuries. While such attacks may not be coordinated, they intend to use mass media to propagate their ideas, inspire other similar actions and provoke fear among their perceived enemies. As such, it is no surprise that this sort of violence first arose in tandem with the emergence of mass media, particularly the mass circulation of newspapers in the 1880s.