Before the slaughter of dozens of people in Christchurch, New Zealand and El Paso, Texas this year, the accused gunmen took pains to explain their fury, including their hatred of immigrants. The statements that authorities think the men posted online share another obsession: overpopulation and environmental degradation.

The alleged Christchurch shooter, who is charged with targeting Muslims and killing 51 people in March, declared himself an “eco-fascist” and railed about immigrants’ birthrates. The statement linked to the El Paso shooter, who is charged with killing 22 people in a shopping area earlier this month, bemoans water pollution, plastic waste and an American consumer culture that is “creating a massive burden for future generations.”

The two mass shootings appear to be extreme examples of ecofascism – what Hampshire College professor emeriti Betsy Hartmann calls “the greening of hate.”

Many white supremacists have latched onto environmental themes, drawing connections between the protection of nature and racial exclusion. These ideas have shown themselves to be particularly dangerous when adopted by unstable individuals prone to violence and convinced they must take drastic actions to stave off catastrophe.  […]