 He was awarded the Military Medal for gallantry during the Korean War.After Hanna left the regular Army, he joined the North Irish Militia, Territorial Army unit (TA) and later the Ulster Special Constabulary, commonly known as the B Specials, which was a reserve police force in Northern Ireland.Upon their disbandment in May 1970, he then became a part-time member of the newly formed Ulster Defence Regiment (UDR).