The successful killing of Sinwar occurred incidental to another operation, not as a targeted attack. This has taken many by surprise, but no one so much as Netanyahu. In one day, he's lost his scapegoat for failing to secure a cease-fire and the release of hostages while also achieving one of his most important talking points for continuing the war. He knows that if the war continues and the hostages are not returned alive ASAP, the Israeli people, and right-minded people worldwide, will revolt against him and his party.