From April to September 1982, the Queen's son, Prince Andrew, served with British forces in the Falklands War, for which she reportedly felt anxiety and pride. On 9 July, she awoke in her bedroom at Buckingham Palace to find an intruder, Michael Fagan, in the room with her. In a serious lapse of security, assistance only arrived after two calls to the Palace police switchboard. After hosting US President Ronald Reagan at Windsor Castle in 1982 and visiting his California ranch in 1983, the Queen was angered when his administration ordered the invasion of Grenada, one of her Caribbean realms, without informing her.