First off, the only people arrested near the WTC on 9-11 were Israelis, three of whom were Mossad agents. These were the so-called "Dancing Israelis".
Second, Carl Cameron's four-part story on the Israeli spy network being arrested at the time of 9-11 included a statement from a US Government official that evidence exists linking the above Israelis with 9-11, but that the US Government has classified it.
Third, why would Saudi Arabia attack the US? They have trillions of dollars invested here, which would be lost in the event of a confrontation, and more to the point, if the Saudis wanted to destroy the US, all they have to do is ask for their investment money back, and they could crash the entire US financial system, and it would be perfectly legal to do so.
Of course, Israel, which takes vast sums of money out of the US, resents the influence that the Saudis enjoy because of the money they put into the US, and would have a strong motive (as well as an established track record of such dirty tricks) to carry out 9-11 to blame on the Saudis for both political and financial gain.
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