Former 9/11 Commission legal counsel and border security expert, Janice Kephart has been intimately involved in the case for years and even submitted an affidavit. She sums up the case in a Washington Times piece:
On July 23, 2001, a former senior Iranian intelligence officer, Abolghasem Mr. Mesbahi, learned that Iran’s plan to strike the United States had been activated. Mr. Mesbahi knew it was important and real because he had worked on this plan previously, when he had helped set up Iran’s intelligence service, the MOIS, as far back as the mid-1980s. Mr. Mesbahi - known outside Iran as one of a core of “Assassins”- told German intelligence, which had given him protected status as a key witness in German prosecutions of brutal Iranian assassinations of dozens of dissidents.As I wrote about here, Mesbahi was a huge piece of the puzzle that showed Iran's involvement. The other huge piece to the puzzle was a Hezbollah leader named Imad Mughniyah; he was that group's liaison with al-Qaeda:
On Aug. 13, 2001, Mr. Mesbahi received greater specificity as to the plot. The coded messages from former colleagues inside Iran revealed that the longtime plan to crash civilian airliners into American cities had been activated. Again, the officer told his German handlers, who responded that they would convey the information - we do not know if they did or to whom or exactly what information they might have passed on - and the Germans would let Mr. Mesbahi know if there were any developments. On Aug. 27, 2001, Mr. Mesbahi once more received confirmation that the plan was in motion, and the messages indicated a German connection. The 9/11 Commission would later confirm that key 9/11 liaison Ramzi Binalshibh and pilots Mohammad Atta and Ziad Jarrah were all German residents leading up to Sept. 11.
After Sept. 11, Mr. Mesbahi approached an American he knew was well-versed in Iranian affairs and told him of his foreknowledge of the Sept. 11 plan and how the plot to crash the then existing Boeing 747 aircraft into New York, Washington and Chicago had evolved in Iran years prior. The Pentagon, White House and World Trade Center had been on the hit list. Back in the 1980s, Iran had decided, he said, that to defeat the United States, it needed to engage in asymmetric warfare.
How did Iran get involved with al Qaeda? According to the Lopez-Tefft affidavit and other expert affidavits in the case, as well as convicted former Osama bin Laden bodyguard Ali Mohamed, the alliance began in 1993 in Khartoum, Sudan, in a meeting between Iranian and Hezbollah leadership with al Qaeda leadership to bridge the Shiite-Sunni gap and address common goals of defeating Israel and the United States. A direct working relationship was created between Iran’s MOIS; Hezbollah’s operational chief and key liaison with Iran, Imad Mughniyah; Osama bin Laden; and other senior al Qaeda leadership. Mughniyah himself was responsible for more than 100 terrorist incidents until his assassination in Syria in 2008.This trial appears to have revealed the smoking gun of the 9/11 attacks and Iran is holding it.
Read it all.