BEIRUT (AP) — He is among the very last survivors of his Gaza family, a clan so close they knew without thinking how blood and marriage bound them across generations and city blocks. Then, branch by branch, 173 of Youssef Salem’s relatives were killed in Israeli airstrikes in a matter of days in December. By spring that toll had risen to 270. Bones and flesh strewn over the ruins of family homes. Blond curls of a young cousin peeking through bricks. Unrecognizable bodies piled on a donkey cart. Lines of burial shrouds. These images are what survivors are left with...