Yeah, it's an apocalyptic ****-up. But believing that Hamas actually had some offensive capability ran contrary to the narrative they were trying to tell, and which they seem to convinced themselves of, which is that Hamas was cowed, and consequently they could largely ignore Gaza beyond the occasional retributive strike, and redeploy a bunch of IDF personnel to the West Bank to ensure that settlers didn't come to any harm as they carried out pogroms.
There are definite parallels to the US approaching 9/11. They had strong intelligence that al-Qaeda intended to launch a strike in the US. They even had some hints of what they attack might look like, and they had some of the hijackers under surveillance. But they also, for some reason, believed that a large-scale coordinated attack on American was simply unthinkable, and interagency rivalries resulted in poor intelligence-sharing. I wouldn't at all be surprised if the story here was that the Mossad (external intelligence/security), Shin Bet (internal), IDF and the government weren't being terribly cooperative, either with each other or even within the orgs...Bibi's anti-democratic law and the resultant protests have exposed some deep divisions.
In a just world, that sort of ****-up would discredit each and every member of the government, given that their whole shtick is that they need to brutalize Palestinians to keep Israel safe. In reality, it'll only make them more popular, given that they'll now argue that only brutalizing Palestinians more will keep Israel safe.
