I don't believe that Holder made the decision without Obama's approval.
No doubt.
It's a huge mistake by the Obamanites and will do immeasurable damage to the nation as a whole.
KSM may not even make it to trial on any one of several technicalities. Even if he does, he won't be the one on trial. Any good defense attorney will instead put the United States, the Bush administration, the CIA , and our armed forces on trial.
A circus, if there ever was one.