Yes, FM. I spent over ten years researching it, and the Israeli state was definitely involved. Absolutely no question. Additionally, prominent government figures like Cheney and Rumsfeld almost certainly knew about it in advance.
There are credible reports that Mohammed Atta was a Mossad asset, there is the matter of the Israeli spy ring busted taking plans of federal buildings, some of the purported hijackers lived on the same street as Israeli intelligence agents, and of course there were also the five "dancing Israelis" busted for celebrating the attacks while documenting them in real time, who also later flagged positive for explosives residue.
Additionally, the hijackers were trained to fly by an ex-IDF pilot living in America and some of them spent time partying on the private boat of a prominent Israeli entrepreneur.
How they got away with it is still a mystery to me. It speaks volumes about the gullibility of Americans and the blind trust they have in government.