I try not to be too conspiratorial, despite the appeal it has for us all. But I think there's a more than probable chance that this was the goal for Israel all along.
What I mean is that, while American media has been mostly hush-hush about it (because you can't be "anti-Semitic"), we know for a fact that Israel knew Hamas was plotting the Oct. 7th event. Maybe they didn't know exactly what date, but they knew.
Given the capabilities the IDF and Mossad have demonstrated with taking out Hezbollah and Iranian leadership (I saw the 60 Minutes episode couple weeks ago, where two Israeli IDF figures, who were almost certainly approved by Israeli leadership to appear there, said the Hezbollah beeper and walkie-talkie thing was a 10 year operation), there's no way they did not know Hamas was going to attack.
They allowed it to happen. The people killed in the process and the hostages be damned.
I think they allowed it to happen precisely for this moment.