Russia’s escalating, if struggling, invasion of Ukraine provides an ugly reminder of Europe’s war-prone past.

In threatening supplies of energy, crops and other necessities, it also resurfaces something globalization obscured: Our dependence on complex, free-flowing trade routes. Germany’s reliance on Russian gas to ease its energy transition is one of the more obvious examples laid bare. But this summer’s Sri Lankan unrest, and the ousted president’s frantic calls to Moscow for oil before he fled, also demonstrated how prices transmit crisis.

The post-war order of free trade backed by U.S. naval supremacy (and security guarantees) has looked shaky for a while. The Ukraine war offers a glimpse of what came before. In the new normal — or reversion to the old normal — there’s a sharper strategic edge to dependence on imports of vital stuff from elsewhere.