A Senate hearing Wednesday with Big Tech CEOs became the backdrop for Democrats and Republicans to swap accusations of inappropriate electioneering.Why it matters: Once staid tech policy debates are quickly becoming a major focal point of American culture and political wars, as both parties fret about the impact of massive social networks being the new public square.Driving the news: The Senate Commerce Committee convened a hearing Wednesday with the CEOs of Facebook, Twitter and Google, ostensibly to discuss Section 230 of the Communications Decency Act, which protects online platforms against lawsuits over moderation decisions and user-posted content. Lawmakers spent much of the session, however, litigating those very moderation calls and the content of the posts.Republicans including Sens. Ted Cruz and Marsha Blackburn accused the companies of using their moderation practices to tip the political scales against Republicans.Examples cited included Twitter and Facebook limiting the reach of stories and posts about files apparently misappropriated from Hunter Biden, as well as flagging false claims from President Trump on voting and COVID-19. Democrats including Sens. Ed Markey and Tammy Duckworth argued Republicans are making empty claims meant to support a threat to take away Section 230 or otherwise punish the platforms — all to influence them against cracking down on misinformation from Trump and other conservatives.This, the Democrats maintained, is a deliberate scare tactic aimed at boosting Trump and other Republicans' electoral fortunes.What they're saying: "Who the hell elected you and put you in charge of what the media are allowed to report?" Cruz rhetorically asked Twitter CEO Jack Dorsey. "Republicans can and should join us on the real problems posed by Big Tech," Markey said. "But they want to feed a false narrative about anti-conservative bias so it will stand idly by again."Meanwhile: Sen. Shelley Moore Capito was one of few senators to actually get into what changing Section 230 would entail, asking the CEOs how they decipher language in the law that gives them a license to remove "otherwise objectionable" content on top of material that's obscene, violent or harassing.Zuckerberg said Facebook would be seriously constrained in its ability to delete most objectionable material such as hate speech and misinformation without that provision.Separately, Zuckerberg reiterated that's he's concerned about civil unrest around the upcoming election.