
Basically the source is a cable from the US embassy in Israel to the State Dept, and WaPo has seen the cable. Israeli intel says that the IRGC would “[have] the upper hand” if protesters took to the streets. They also said this regime is willing to “fight to the end”. Then there’s a bunch of recap of the whole situation and quotes from public statements
It also seems like Israel underestimated the regime, which surprised some experts who say Israel’s intel on Iran is usually top-notch and that they’ve deeply infiltrated the regime. Israel assesses that Mojtaba is more hard-line than his father and very much still in charge. They think the regime might moderate its views if he’s taken out, but he’s “stubborn” and he would need to be “taken down from within”. I have a gift link if you want to read the article