Social media platforms connect billions, but their business models often amplify societal harm through misinformation, which is linked to polarization, violence, and declining mental health. Current governance frameworks, such as the U.S. Section 230 and the EU Digital Services Act, delegate content moderation to corporations. This creates structural conflicts of interest because misinformation drives engagement, and engagement drives profit. We propose a public utility model for social media governance that prioritizes the public good over commercial incentives. Integrating legislated content removal with democratic content moderation, the model protects free expression while mitigating societal harms. It frames social media as sovereign digital infrastructure governed through democratic oversight, transparent algorithms, and institutional safeguards.