James Joyner argues against a civilian trial for KSM:

[T]hese men are not citizens of the United States. Second, they’re accused war criminals. They simply should not be tried in U.S. civilian courts. Rather, they should either be held accountable in a Nuremberg-style international forum or treated as war criminals by a U.S. military tribunal under the mechanisms provided by Congress and approved by the Supreme Court. Aside from the virtual certainty that the trial will devolve into a media circus, there’s an incredibly good chance that Mohammed and his comrades will go free. The fact that KSM was repeatedly waterboarded would seem to taint any subsequent evidence, including his own confession.

I think it's a potentially brilliant move. I do not believe for one moment that this case was brought in a civilian court without sufficient evidence to convict KSM of criminality to put him away for good. But what an open civilian case will also do - and it's why a war criminal like John Yoo is so apoplectic - is reveal the extent to which the brutal torture of KSM was unnecessary, and led to the government's inability to prosecute him to the full extent of the law.

It will be a civic lesson to America and the world. It will show the evil of terrorism and the futility and danger of torture. It will be a way in which Cheney's torture regime can be revealed in all its grotesque excess at the same time as KSM's vile religious extremism is exposed for its murderous nihilism. That all this will take place in New York - close to where the mass murder took place - is a particularly smart touch.

This will, then, be a Nuremberg-style event - because it will pit Qaeda barbarism against the cooling, calm and resolute nature of real Western justice in the clear light of history. But it does one more critical thing. It reveals a new confidence in ourselves and the Western way of life.