Hussein began his teaching career at Lebanese University in 1990. He also taught at the command college of the Lebanese Armed Forces. He served as minister of state for social affairs from 9 November 2009 to January 2011. He was one of five ministers appointed by President Michel Suleiman. In addition, Hussein was one of the independent and Shia members of the cabinet. His resignation from office led to the toppling of Saad Hariri's cabinet, since ten ministers, who were the members of 8 March alliance, had resigned before. They resigned due to their objections to the UN investigation into the 2005 assassination of Rafik Hariri.