Saint-Paul-lez-Durance, France — As global energy prices soar, 35 countries are working together at a sprawling facility nestled in the French countryside to try to create a new source of unlimited, clean power for the entire planet. Their ambition is to harness the power of the stars: nuclear fusion. Some of the participating countries — which include the United States, Russia, China, India, South Korea, Japan, and the nations of the European Union — are frequent collaborators, but some are major adversaries on the world stage. Russia's invasion of Ukraine has prompted an unprecedented barrage of sanctions against Moscow from…