If you thought the spat over Michael Moore’s Planet of the Humans couldn’t get worse, you don’t spend much time online. But this much worse? It seems Michael Mann has accused Moore of being a Russian stooge. See, Climategate was Kremlin disinformatsiya and…

The fact that Michael Moore has suddenly said something with which you sympathize should not lead to uncritical endorsement of the way he said it, or his habitual views of the world. But the fact that Michael Mann has suddenly said something extremely offensive might lead one to a critical evaluation of the habitual argumentative style of such people including his former allies. Surely Moore can be wrong without being evil. And so can others Dr. Mann disagrees with. Can’t they?

Likewise, surely humans can be on the wrong track without being deplorable. Yet one of the points in Moore’s film that is deeply disturbing is the insistence that there are way too many of us and a bunch have got to go. Ecosystems certainly are under stress, and Moore is not wrong that human domination of the planet is on a scale, and accompanied by changes in the land, that are unprecedented. (The classic image of the world from space at night, with the incredible patches of light, is quite unlike anything any other species has wrought or conceivably could, as are the rivers that once caught fire in North America and those choked with plastic in Asia today.) All true. But can we not find a constructive way forward?

Many people seem eager to say no. And thus if you did and do find Michael Moore’s and other radical environmentalists’ anti-human views surprising, we regret to say that such ideas are very widespread among Deep Ecologists and some shallow ones too. And while Extinction Rebellion may at least have the idea of personally going first, too many others don’t.

Arguments should be evaluated on their merits. But one of their merits, or weaknesses, is the extent to which they appear to have nastiness hard-wired in. American writer David Horowitz, a New Left Marxist from the 1950s into the 1970s, later wrote sorrowfully that “What motivates radicals is not compassion for the lost soul of mankind, but the hatred of human beings as they are.” And when two groups with that quality in common have a falling-out, it’s not surprising that it’s very ugly indeed.