 Stewart collaborated with Hertzberg on virtually all the major speeches of the Carter Presidency from 1978 onwards, including the landmark presidential address, the Oval Office "Crisis of Confidence" talk of July 15, 1979.Stewart was directly involved in multiple Presidential projects including the Strategic Arms Limitation Talks (SALT II), energy, fiscal and monetary policy, human rights issues, the response to the Soviet invasion of Afghanistan, the first visit to the White House by a Pope in United States history by Pope John Paul II in 1979, three State of the Union addresses, and the farewell speech of President Carter to the nation.Following his time in the White House, Stewart continued his work in politics as a director of the New York Urban Coalition, and as an advisor to various business, government, and academic forums including the Committee for a Responsible Federal Budget, the National Bureau of Economic Research, the American Business Conference in Washington DC the International Commission for Central American Recovery and Development, the Council on Competitiveness, and the Defence Science Board.