A quarter of a century since 9/11 – history’s most deadly terrorist attack – and we’re again seeing horrific scenes as even bigger towers crumble and crush all that lie in their shadow. These new collapses aren’t of human structures, they are of our high mountains and their glaciers, often described as the water towers of the world. But their demise is every bit as much a story of human folly as the fall of the Twin Towers.











