Two weeks after his recess appointment, CMS Administrator Don Berwick,MD, is still struggling to tamp down a furor over past statements in which he discussed the rationing of health care and expressed affection for the British health care system. And he is finding his ability to do his job clouded by the circumstances of his appointment, with many Republicans in open revolt over President Obama’s decision to place him in the post without a Senate confirmation vote. Berwick never had a confirmation hearing and has not responded publicly to critics. The White House declined to make him available for an interview. But friends and allies said he was preparing a point-by-point rebuttal, most likely to be delivered when he first testifies before Congress. He wants to focus on the work of his agency, which finances health care for one in three Americans and has a budget bigger than the Pentagon’s.