The GDR saw it as the international frontier of a sovereign state – a defensive rampart against Western aggression.[47] In Grenzer ("Border Guard"), a 1981 East German Army propaganda film, NATO and West German troops and tanks were depicted as ruthless militarists advancing towards East Germany. Border troops interviewed in the film described what they saw as the rightfulness of their cause and the threat of Western agents, spies and provocateurs. Their colleagues killed on the border were hailed as heroes and schoolchildren in East Berlin were depicted saluting their memorial.[48]