President Joe Biden told an audience of conservation and environmental groups Wednesday that their work has never been more important at a time when they are battling the greatest threat facing future generations. Speaking at the annual Capital Dinner of the League of Conservation Voters, Biden told the supportive audience there are “a lot of threats to our children, grandchildren and great-grandchildren” but climate change “is the only truly existential threat.” He said the audience members and his administration had done good work in combatting the threat but everyone needed to “finish the job.”