Who are the bad guys in the Syrian civil war? You can follow observable reality and conclude that the distinction goes to the nation’s genocidal despot, Bashar al-Assad, who has slaughtered nearly half a million of his own people in a prolonged and bloody civil war. Or you can believe Russian propaganda that, in an effort to protect its puppet in Damascus, is promoting a conspiracy theory that the real villains are the White Helmets, the non-profit organization dedicated to rescuing civilians and documenting the war’s ravages. These first responders, claims the Kremlin’s distortion machine, are secretly in the pocket of unnamed terrorists, and they fake the photographic evidence they provide in order to make sweet old Assad look bad.

If you’re wondering who would believe such an idiotic and patently preposterous claim, wonder no more: In a concert Friday night, Roger Waters, the former Pink Floyd frontman and obsessive anti-Israel activist, launched into a tirade that sounded every bit like Moscow’s talking points.

“The White Helmets are a fake organization that exists only to create propaganda for the jihadists and terrorists,” Waters roared from the stage in Barcelona, announcing that a supporter of the group had audaciously asked to speak to the crowd about the murderous chemical attack that left scores of Syrian dead.

“If we would listen to the propaganda of the White Helmets and others we would be encouraged to encourage our governments to go and start dropping bombs on people in Syria,” Waters continued. “This would be a mistake of monumental proportions. What we should do is be persuading our governments to not to go and drop bombs on people.”

You can watch the embarrassing scene for yourself below. It’s a useful reminder of how conspiracy theories work: Once you, like Waters, buy in to the pernicious logic of BDS and believe, contrary to common sense and basic decency, that the Jewish state, alone among all of the world’s nations, should be singled out for calumny, you may as well also believe that those photos of dying Syrian children are fake news. Hateful minds have little room for logic.