Melkonian had no prior service record in any country's army before being placed in command of an estimated 4,000 men in the First Nagorno-Karabakh War. He had largely built his military experience beginning from the late 1970s and 1980s, when he fought in Lebanon with ASALA. Melkonian fought against various factions in the Lebanese Civil War and against the IDF in the 1982 war.