Stephen Miller is an American political advisor known for his staunchly conservative and nationalist views on immigration. He served as a senior advisor to President Donald Trump, playing a key role in developing and implementing controversial policies such as the travel ban targeting several Muslim-majority countries and the "zero tolerance" policy that led to family separations at the U.S.-Mexico border. Prior to his White House role, Miller worked as a staffer for Republican members of Congress and was a vocal critic of multiculturalism and illegal immigration. His policies and rhetoric have been widely criticized by human rights organizations and progressive groups.