 In early 2000, Nilsson served as head of the Planning Department of the Joint Operations Command ("Operationsledningen", OPL) in the Swedish Armed Forces Headquarters in Stockholm.Nilsson was appointed Inspector General of the Air Force on 30 June 2000 and head of the Air Force Tactical Command.As the air force chief, Nilsson in 2001 launched an open dispute with the Social Democrats regarding the disbandments of air force wings.