They were to bin Laden and Al Quaeda. When the one eyed mullah was tried in New York for bombing the WTC in 1993, all sorts of what should have been classified information on the engineering of the WTC became public knowledge.
Did that help the attackers decide where to crash the planes in order to do the most damage? We will probably never know but it damn sure could have.
How about if US operatives are identified? Witnesses? The jury?
One of the purposes of the tribunal is to keep classified and secret what must remain so.
I do approve of military courts.