AMERICANS WENT to sleep on August 3rd reading about a mass shooting that had left 20 people dead in El Paso, Texas, and woke up to news of another shooting overnight in which nine people, plus the shooter, had been killed in Dayton, Ohio. Both come just one week after a gunman killed three people and himself at a festival in Gilroy, California. The El Paso massacre was the deadliest mass shooting in America since November 2017, when a gunman in Sutherland Springs, Texas, killed 26 people. As of Sunday morning, there have been 32 shootings with three or more victims in America this year.

Shortly before opening fire, the El Paso shooter—a 21-year-old from suburban Dallas named Patrick Crusius—appears to have posted a manifesto on 8chan, a messageboard popular with the far right (8chan’s moderators quickly deleted it; other 8chan posters have repeatedly reposted it). The manifesto opens with a statement of support for Brenton Tarrant, who earlier this year killed 50 people at two mosques in Christchurch, New Zealand, and Mr Tarrant’s manifesto, which propounded a belief in “The Great Replacement”, a far-right conspiracy theory that holds that feckless Western elites are “replacing” those of European descent with non-white immigrants.

Mr Crusius wrote that his attack was “a response to the Hispanic invasion of Texas”, a state that until 1836 was part of Mexico. El Paso itself has long been majority Latino. It forms part of a huge binational conurbation, of which Juárez, just across the border in Mexico, comprises the larger part. He claimed that Texas risks becoming “a Democrat stronghold”, but condemned both major political parties. (He suggested, however, that “At least with Republicans, the process of mass immigration and citizenship could be greatly reduced.”) He also sounded anti-corporatist themes and warned of environmental collapse and automation of jobs. He objected to being called a white supremacist, but railed against immigration, diversity and “race mixing”. And he advocated dividing America “into a confederacy of territories with at least 1 territory for each race”. In essence, his manifesto is a warmed-over, less coherent version of what the Christchurch murderer wrote, but with less irony and more self-pity.

Strictly speaking, Mr Crusius appears to have acted alone: he was the sole shooter, and mentions no help in planning or carrying out the attack. But that does not make him a lone wolf. His murder has a noxious lineage. The Christchurch killer inspired him, just as Anders Breivik, a Norwegian right-wing terrorist who murdered 77 people in and near Oslo, inspired Mr Tarrant. In recent years Western countries have seen a surge in far-right violence. Between 2010 and 2017, America suffered 2.4 times as many right-wing terror attacks as jihadist ones. Online message boards make it easier for terrorists to forge operational links across national boundaries. They also provide fertile soil for radicalisation.

President Donald Trump called the El Paso shooting “an act of cowardice”. Mr Crusius said his “opinions on immigration, automation and the rest predate Mr Trump and his campaign for president”. But no president has campaigned on immigration fears as explicitly as Mr Trump, nor has any mainstream American politician—much less a president—as directly stoked the flames of racial grievance.

Less is known about the Dayton shooter, who was killed less than a minute after opening fire. He used a .223 “long gun” with high-capacity magazines, which are legal in Ohio and 41 other states. The Gilroy killer’s motive is similarly unclear, though in a deleted social-media post he appears to have ranted about “hordes of mestizos”. What is depressingly clear, however, is that as long as America makes it easy for young, angry men to buy weapons of war, it should expect more mass shootings.