Al-Shiqaqi and the other founding fathers of PIJ … succeeded because of their presence on the ground and being part of the Gazan social and political fabric – necessary to create vertical ties between the leadership and the local population. Combined with strong horizontal ties, this enabled the PIJ nucleus to develop into a locally grounded armed movement. Yet… an additional important factor for this development was the Israeli prisons and the recruitment of former secular-nationalist militants.

— History of Palestinian Islamic Jihad by Erik Skare (Page 69)