Western leaders are preparing for the possibility that Russian natural gas flows through the key Nord Stream pipeline may never return to full levels. WSJ’s Shelby Holliday explains what an energy crisis could look like in Europe, and how it might ripple through the world. Illustration: David Fang BERLIN—German investigators have determined that the series of explosions along key undersea gas pipelines from Russia to Europe were likely caused by sabotage, according to officials familiar with the probe, adding weight to similar preliminary findings by Swedish officials . German investigators haven’t been able definitively to link the suspected sabotage to any one actor, but some German officials say they are working under the assumption that Russia was behind the blasts. The explosions created leaks affecting three of four pipes that are part of the Nord Stream and Nord Stream 2 pipelines, built under the Baltic Sea to transport […]