In Avengers: Infinity War — henceforth known as Thanos: The Hands of Fate — the mad Titan Thanos believes himself to be the hero, eliminating half of every planet’s population to curb ecological disasters. This plan is dumb as hell, of course. Curbing over-consumption, not population, would be a long-term solution. Half of a population that over-consumes is still going to create the same ecological disaster, just not as quickly. But a multi-pronged campaign to increase production efficiency, shift to clean energy, and reduce waste isn’t nearly as fun as snapping people to death, we suppose.
Nonetheless, Thanos claims his plan is working, and part of his evidence is telling Gamora her home planet (Zehoberi) is now a paradise thanks to his murdering half of her people, including her mother:
Thanos: “I saved you.”
Gamora: “No, no, we were happy on my home planet.”
Thanos: “Going to bed hungry. Scrounging for scraps. Your planet was on the brink of collapse. I was the one who stopped that. You know what’s happened since then? The children born have known nothing but full bellies and clear skies. It’s a paradise.”