These working groups could sow discord if Mr. Biden doesn’t shift far enough to the left. Before Rep. Alexandria Ocasio-Cortez agreed to be a co-chairman of the climate task force, she consulted with “the Climate Justice community” and pledged to be “fully accountable to them and the larger advocacy community during this process,” according to a spokeswoman. Note to Mr. Biden: AOC’s loyalties are with her “social-justice warrior” friends, not you.

Many of the members picked by Mr. Sanders have extreme views. Varshini Prakash, a co-founder and executive director of the Sunrise Movement, which has led the push for the Green New Deal, serves on the climate committee. Sunrise wants to end fracking immediately, ban drilling in federal waters and on federal lands, prohibit exports of oil and natural gas, and set a 10-year timetable to phase out all oil and gas drilling permanently. This is a political middle finger to not only Texas, but Pennsylvania, too.

Other task-force co-chairmen are drawn from groups such as the National Immigration Law Center, which favors full access to welfare benefits for illegal aliens, and Demos, the think tank that works to make it harder for states to purge registration rolls of dead voters and former residents. The task-force chairmen and members also include outspoken advocates for Medicare for All, “free” college, student-debt forgiveness, defunding the Border Patrol and the bizarre but trendy Modern Monetary Theory. (Sanders appointee Stephanie Kelton says having its own printing press means the government doesn’t have to “worry about going broke.”)