Democrats must kill the filibuster and make the Senate great again. By Adam Jentleson Mr. Jentleson is the author of “Kill Switch: The Rise of the Modern Senate and the Crippling of American Democracy.” Jan. 20, 2021 Under Mitch McConnell as minority leader, Senate Republicans used the filibuster to block President Barack Obama’s agenda. Credit...Damon Winter/The New York Times Bumping Senator Mitch McConnell to the minority increases Joe Biden’s odds of passing his agenda, but there is a catch. In the Senate in recent decades, the filibuster has morphed from the long-winded speeches portrayed by Jimmy Stewart in “Mr. Smith Goes to Washington” into a silent but lethal tool that lets any one senator raise the threshold for passing bills from a simple majority (where the framers set it) to a supermajority of 60 votes.