Yahoo: Secretary of Energy Steven Chu in 2011 (Larry Downing/Reuters)Energy Secretary Steven Chu, a Nobel Prize-winning physicist frequently the target of Republican criticism, announced Friday that he was stepping down in the latest shake-up of President Barack Obama's Cabinet. Chu, who disclosed his decision in a letter to Energy Department staff, frequently clashed with GOP lawmakers over gas prices as well as government backing for green-energy companies like the failed firm Solyndra.
In his letter,...