By JOSEPH KRAUSS and SARAH EL DEEB The Gaza Strip is in ruins. There are hills of rubble where apartment blocks stood, and pools of sewage-tainted water spreading disease. City streets have been churned into dirt canyons and, in many places, the air is filled with the stench of unrecovered corpses. Israel’s yearlong offensive against Hamas, one of the deadliest and most destructive in recent history, has killed more than 41,000 people, a little over half of them women and children, according to local health officials.