President Donald Trump picked his new National Security Adviser today. Army Lt. Gen. H.R. McMaster will replace Michael Flynn, who resigned after withholding information about a call with Russia’s ambassador. Tomorrow, Scott Pruitt — another high-profile appointee — will take his job as the head of the Environmental Protection Agency.  Pruitt has a complicated past with his new agency. He sued the EPA 14 times when he the was Attorney General of Oklahoma. The Trump administration has said it wants to move quickly to dismantle some of the Obama administration’s regulation. What can Pruitt do to make this happen?