"The President relies on subordinates in the executive branch to help him faithfully execute the laws and advance the priorities for which he was elected by the American people. Officials in confidential, policy-determining, policy-making, and policy-advocating roles (policy-influencing positions) play particularly important roles in helping him fulfill this constitutional duty. Therefore, ensuring that such employees can be removed for misconduct or poor performance is essential to protecting democratic self-government by an elected President."