In August 2005, Israel left Gaza. Every soldier was withdrawn. Every Jewish settlement was evacuated, in a process requiring 45,000 police and costing $2.5 billion. Politicians staked their reputations on a courageous step towards peace. They hoped Gaza could provide a blueprint of Palestinian autonomy, a precursor to a Palestinian state. Tragically, Hamas chose violence, rejecting the chance to develop Gazan society and opting instead to attack ours. Missiles from Gaza have blighted the lives of Israeli civilians since 2001. The withdrawal should have brought calm, but 5,000 missiles and mortars have since rained down on Israel. As I write,...