Common saying was that Yugoslavia was surrounded by worries or in Serbo-Croatian language BRIGAMA. In this acronym every letter corresponds to a beginning letter of a different neigboring country, so in order: Bulgaria, Romania, Italy, Greece, Austria, Hungary (Mađarska in Serbo-Croatian), Albania. There was a certain amount of paranoia, especially after breaking with Stalin in 1948, which continued all the way practically until the end of Yugoslavia. There were a few very common things said at the time such as Ništa nas ne smije iznenaditi (Nothing may suprise us), and Neprijatelj nikada ne spava (Enemy never sleeps).
You also had a concept of Total National Defense, in which units of Teritorial Defense, which could number up to 3 milion men at one point in time, and included everybody from the ages 15 and up. They would fight a guerrila war, and act in support of more regular forces. We must not forget that in high schools you had subject called Obrana i Zaštita (Defense and Protection), and which included basic marksmanship training, first aid and radio training.
They even went that far, so that Yugoslavia spent roughly 1 percent of its GDP, solely on units and equipment for Teritorial Defense.