When enemies don't exist, they're invented. Hamas is a convenient one. So are Iran, Syria, and Hezbollah.
Achieving regional hegemony depends on inventing enemies, destroying major ones, and eliminating rivals various ways. Balkanizing some into weak statelets substitutes for full-scale war.
Israel's longstanding strategy calls for dividing the entire region along ethnic and sectarian lines. It wants easily controlled satellites.
In 1982, Israeli Ministry of Foreign Affairs senior advisor Oded Yinon published "A Strategy for Israel in the 1980s."
Longtime Israeli academic, activist, analyst, and outspoken critic Israel Shahak (1933 - 2001) translated, edited, and retitled it "The Zionist Plan for the Middle East."
Israel modeled it after the Ottoman Empire's Millet (or nation) system. It functioned by letting local authorities govern confessional communities with separate ethnic identities.
Israel wants the region ruled this way. Peace and stability defeat its agenda. Great pains are made to prevent them. Jabari was murdered for that reason. Palestinian divisions and besieging Gaza serve the same purpose.
On November 21, Israel arrested at least 55 Palestinians. Dozens of others followed. Many were Hamas, Islamic Jihad, and Popular Front for the Liberation of Palestine members. Victims committed no crimes.