I did wonder why the Israelis were so keen to take Gaza back?

Oh no!, but are 700k Gazans easy to control? Even 10 are not easy ! What did Israel do in 2005 ? (By 22 September 2005, Israel's withdrawal from the entire Gaza Strip to the 1967 Green Line, and the eviction of the four settlements in Samaria, was completed. In June 2007 Hamas took over the Gaza Strip from the Palestinian Authority.) The rest is history !
(Based on the UN Convention on the Rights of the Child, a child means every human being below the age of 18.) Even at 13-15y, they are throwing stones etc. Which can kill!