Steven Chu, the wonky, Nobel-Prize-winning secretary for President Obama's Department of Energy is stepping down today, after four years of steady but often frustrating progress in a political climate that Chu never fully understood well enough to navigate without stumbling. Trained in advanced physics and biology — not political science — Chu had troubles with Solyndra, the California solar-panel company that in 2011 defaulted on a $535 million loan the Department of Energy had offered it in March 2009. According to Politico, Chu's rocky tenure appears to have influenced Obama's shortlist for his replacement. Consider the potential appointees:

  • Byron Dorgan, a former Senator from North Dakota
  • Bill Ritter, former Governor of Colorado
  • Chris Gregoire, former Governor of Washington
  • Jennifer Granholm, former Governor of Michigan

While Politico also notes "buzz" about MIT physics professor Ernest Moniz, the theme among the above contenders is clear: Obama wants someone who can play politics, a skill set Chu was never all that interested in mastering. Obama will need pure political talent — not empiricism, not academic clout — to push his second-term priority for action on climate change. That, and he has a lot of old white men in his cabinet right now, a fact which Chu's departure offers an opportunity to amend.