US obstruct trial against 9/11 terrorist in Hamburg

[gandalf]

The US policy to make every single bit of information connected to the September 11 attacks a subject of national security that has to remain secret obstructs the trial against Mzoudi in Hamburg.
The court wanted to use as evidence interrogations transcripts of Sheikh Mohammed and Ramzi Binalshib, held in US custody at an undisclosed location. Yesterday the presiding judge read out the letters of US agencies (I think it was the department of Justice) declining to hand over the transcripts. German intelligence agencies seem to have received copies but had destroyed them later.
Why don’t the US support the trial against the suspected 9/11 terrorists? What have they to hide? After all, this is only the second trial worldwide against a suspected 9/11 terrorist.

Interestingly, two journalists of the news magazine “Der Spiegel” who apparently had seen the transcripts will be heard as witnesses. How come that they saw these secret transcripts?
One has to bear in mind that “Der Spiegel” who calls itself an “investigative magazine” furiously tries to ridicule everyone who dares to ask a critical question related to 9/11 as a conspiracy nut. Some weeks ago “Der Spiegel” even run a title story on “conspiracy nuts”: Panoply of the Absurd. The story is even available in English for free. Normally you have to pay for the title stories. But obviously the English-speaking people are to be educated as well about the evil and dangerous conspiracy theories.

(I have not found a link to an English Source up to now)