Plus: Republicans fear anger over data centers will cost them in elections. Sometime in the late 2000s, six-year-old Pim Sullivan-Tailyour was sitting in the back of a car in Thailand when she saw a mountain that had been quarried away. It was the first time she recognized that humans could alter the world for the worse. She carried that knowledge with her, later joining an online group for young people worried about climate change. "I realized that I wasn't alone," she says. She was right: global surveys have found that most kids are anxious about the state of the world.

At the start of the millennium it was widely presumed each successive generation would achieve a higher level of prosperity than the last. Today that is no longer the case. Just 19% of Americans expect their children's lives to be better than their own, while two-thirds believe their country will be economically weaker by 2050. So our zeitgeist is increasingly one of pessimism, from anxiety about the climate crisis to concern over rising inequality. According to the historian Adam Tooze, we are living through a "polycrisis" – where such challenges are not only simultaneous but mutually reinforcing.