Fusion energy — tapping the power of the stars — is on the cusp of getting new federal rules. Why it matters: Regulators increasingly view fusion as fundamentally safer than nuclear fission, helping to pave the way for a substantially simpler permitting process than the one faced by conventional nuclear plants. Driving the news : The federal Nuclear Regulatory Commission is closing the public comment period on the proposed rule  on Wednesday, with a final regulation expected as soon as this fall. The big picture : Fusion electricity doesn't yet exist in reality, but industry leaders see this regulatory move as fundamental to commercializing the technology in the United States in the next decade. "This is a big deal — we've been working toward this for a long time," said Andrew Holland, CEO of the Fusion Industry Association.…