Special Counsel Robert Mueller’s indictment of the Internet Research Agency, a Kremlin-linked troll farm, underscores the significant role that social media played in Russia’s efforts to interfere in the 2016 U.S. election. Although this was an important and welcome step, Americans cannot simply look backward. The social media companies whose platforms were exploited must take action to close off the vulnerabilities that Putin and others have exposed and continue to exploit. Russia’s efforts to undermine U.S. democracy, including via social media, continue today. Taking proactive steps to address vulnerabilities that Putin is exploiting is the best way for these platforms to regain the trust of the American people and avoid government overregulation.