Why Dr. Siddiqui has never been charged with terrorism.

Federal prosecutors obviously felt they did not have enough evidence to convict Dr. Siddiqui for terrorism charges. That doesn't mean she was not a terrorist fixer.
Al Capone was never charged with being a Mafia Kingpin. That doesn't mean he wasn't one.

Let's look at the terrorism evidence against her:

First: She was recorded raising funds for a charitable organization that turned out to have (suspected or proven?) ties to terrorist organizations. So what? Many people worked for or donated money to these organizations. There is no way of proving Aafia had knowledge of these links.

Second: Either her or her husband purchased night vision goggles and maybe body armour. The reports differ on this. Nonetheless, there is nothing illegal about this.

Third: she opened up a post box and the key was later found in the hands of a guy charged with plotting a terrorist act. For this to be a crime, the court would have to prove that the post box was somehow used in the plotting of the terrorist act and that Aafia gave the guy the key with foreknowledge that it would be used to plan a terrorist act. Her first two suspicious activities would not be allowed in court as neither were crimes and could prejudice a jury.

Fourth: Some guy in Sierra Leone claimed to witness her buying “blood” diamonds. One witness is not enough to prove she was there. How can they prove these were “blood” diamonds? How can they prove she knew they were “blood” diamonds? How can they prove she was going to smuggle them? How can they prove she was going to give the proceeds to terrorists? They can’t. They can’t even prove she was there.

Fifth: She allegedly married a guy who is being charged with plotting 911. Well the 911 plotter has not been convicted of terrorism to this date for one thing, and although she denies it and the guy's family confirms it, there is again nothing illegal about marrying a suspected terrorist.

Sixth: She was found with incriminating evidence in her purse the day she was arrested in Ghazni. Chemicals? What chemicals? Whatever chemicals she had was not illegal to possess else they would have added a charge for that. Notes? From what I have heard her notes mention places in New York and mention mass casualties, but they do not formulate a plot in themselves. They seem more like the incoherent ramblings of someone who might hate America, but how can they prove that what she had in her purse would aid a terrorist plot in the US? Can you imagine some suicide bomber waiting to launch his attack on the US but he is waiting for Aafia to show up with her scribbling about the Statue of liberty and mass casualties? “Thanks sis, We couldn’t have gone forward without you.”.

So you can see how adding these 6 things together may give rise to suspicions. Still, no court in America will allow a prosecutor to add 6 non-crimes together to come up with a crime.

plus, Khalid Shiekh Mohammad, named her as a key al Qaeda fundraiser and operative.

Attempted Murder was easiest, since they had the witnesses. I still wonder what happened to those bullets though.