IDF and Mossad are indeed state of the art in border security and intelligence. Giving them the benefit of the doubt as a whole, there must have been at least some crazed, apocalyptic faction within one or both of those entities that purposefully allowed for this LARGE scale planning outside their borders and execution within their borders to proceed uninterrupted.

Meanwhile the neocons over here, with their histrionic outrage are implicitly rejoicing over the tragedy, since this is one big step closer to a decades old wet dream of invading / destabilizing Iran. It is good to recall Wesley Clark's statements back in the 2000s about having been privy to plans going back to the 90s to have multiple other nations on the neocon hit list, below Iraq, for invasion/destabilization: Afghanistan, Iran, Syria, Libya, etc.

And their domestic allies and supporters? Mainly all the politically "conservative" Western evangelicals under the religious psy op of Dispensational / Second Coming madness, which is in perfect geopolitical alignment with British + Israeli Zionism, including the Israeli zealot faction who are on board with military violence as the means of ushering in their Messiah. How convenient.