During the 1992 presidential campaign, he was one of Clinton's chief foreign policy advisers. Lake later served as National Security Advisor (1993–1997). In the aftermath of the Cold War, Lake advocated a policy of "enlargement" of the number free market democracies. Told by the White House to sell his stocks in energy companies when he took the office in 1993, Lake did not do so. When Clinton decided in 1994 to allow Iran to arm the Bosnian army, Lake admitted he made a mistake when he didn't push to inform Congress of the decision.