Hamas on Saturday represented an equally stunning intelligence failure by Israel that involved undetected warnings, overwhelmed missile defenses and a slow response by apparently unprepared military forces, former and current U.S. officials said.
American officials said Hamas had achieved a complete tactical surprise, reflected in a death toll of at least 700 Israelis.
The Palestinian militant group sent hundreds of fighters through breached walls, breaking through with bulldozers and then killing civilians and soldiers in shooting sprees that went on for hours.
None of Israel's intelligence services had specific warning that Hamas was preparing a sophisticated attack that required coordinated land, air and sea strikes, according to an Israeli defense official and American officials. While the attack also surprised many Western intelligence agencies, they do not track Hamas' activities as closely as Israel or Egypt do.
The success astounded American officials with experience in the region.
Over the years, Israel has set up a network of electronic intercepts, sensors and human informants throughout Gaza, which is about half the area of New York's five boroughs. Israel and its neighbors have invested heavily in trying to track and block Hamas' networks, often intercepting shipments of missile components.
That past success has made all the more urgent a series of questions about Israel's failures Saturday.
Why was Israel's Iron Dome missile defense system, now a dozen years old, apparently overwhelmed by the barrage of inexpensive but deadly missiles at the opening of the attack? How did Hamas manage to build such a big arsenal of rockets and missiles without Israeli intelligence detecting the growing stockpile?
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