The U.S. nuclear energy sector’s dependence on Russian uranium created during a failed Obama-era reset with Moscow is coming back to bite Americans as the Kremlin moves to block future exports of the vital fuel.  Vladimir Putin’s new restrictions on uranium exports to the U.S., announced last week, come as the country’s war in Ukraine continues to heighten tensions with the United States and the West. His announcement created an immediate impact, as uranium prices soared and...