The author of “Takedown: Art and Power in the Digital Age” explores what the past can teach us about the current eco-protest wave.

Tomato soup. Mashed potatoes. Glue and red glop. Whatever next?

Climate activists eager for global attention have found a new platform on which to vent their rage: masterpiece paintings by Botticelli, Constable, Van Gogh, Monet, and Vermeer.

Wearing t-shirts emblazoned with anti-oil slogans, they have flung canned tomato soup at Van Gogh’s Sunflowers, smeared mashed potatoes over Monet’s Haystacks, and glued themselves to Vermeer’s Girl With a Pearl Earring while a thick red goo was poured over them.

The Musée d’Orsay in Paris nearly became the scene of another eco-attack last week, when a climate activist tried and failed to throw soup at paintings by Van Gogh and Gauguin. By the time this piece is published, still more attacks may have taken place.

The aim of the activists is to get the message out loud and clear: unless industrialized nations act quickly and radically to cut carbon emissions and stop all new oil and gas projects, the world will fall to pieces. “We are in a climate catastrophe, and all you are afraid of is tomato soup or mashed potatoes on a painting,” yelled a German activist after daubing Monet with puree. “When will you finally start to listen?”

Vandalism of art is nothing new, as I write in my book Takedown: Art and Power in the Digital Age, released earlier this year. The book shows how Western art is becoming more and more democratic, inclusive, and accessible—and more and more exposed to attack.