After finishing his army service in the Engineering Corps and Army Intelligence, Jack was recruited into the Israeli security establishment where he worked in a number of different operational and administrative positions associated with National Security. He worked in several different departments and divisions covering a wide range of operational and professional disciplines. During these years he progressed through a number of senior managerial posts until retiring as  a Deputy Divisional Director. During his long career Jack was directly responsible for a number of major projects which contributed significantly to Israel's security. He is a currently a member of the IDSF and a Senior Fellow at the David Institute.