All 20 remaining living hostages held in Gaza and scores of Palestinian prisoners held by Israel have walked free as part of a ceasefire pausing two years of war. The conflict decimated the Gaza Strip, killed tens of thousands of Palestinians, triggered other conflicts in the Middle East, and had left scores of captives in militant hands. Speaking to parliament, Israeli Prime Minister Benjamin Netanyahu declared he was “committed to this peace.” That raised hopes that the ruinous war might come to an end. But fundamental questions remain over when and how.