Kristi Noem is on her way out at the Department of Homeland Security after a tenure marred by personal controversies and an unpopular immigration crackdown. The big picture: Noem has long been a target for Democrats, but her leadership also angered some congressional Republicans. She becomes the first Cabinet secretary to be removed from their post in President Trump's second term.Driving the news: Trump announced Thursday that he plans to tap Sen. Markwayne Mullin (R-Okla.) to replace Noem.Noem...