This is definitely the correct course of action. We are not at war, and KSM is not a war criminal. Terrorism is a criminal act as defined by Federal Statute.
Holding a civilian trial will take away from the Public relations/Information Operations campaign by terror groups. It will show that the rule of law and our system of justice is superior; that we do not have to invent extra-legal, parallel systems of recourse based out of fear and power.
We have successfully tried and incarcerated terrorists in the past using our Constitutionally mandated system of justice, with the requisite oversight. I have a feeling that people upset with a civilian trial of KSM are more worried that it highlights the failures of previous administrations and their boastful claims of bringing terrorists to justice.
Now let's square my eminently rational and logical elucidations with the knee jerk, chest thumping grade school rantings of Caribou Barbie [Sarah Palin] courtesy of Think Progress:
Horrible decision, absolutely horrible. It is devastating for so many of us to hear that the Obama Administration decided that the 9/11 terrorist mastermind, Khalid Sheikh Mohammed, will be given a criminal trial in New York. This is an atrocious decision. [...]
Criminal defense attorneys will now enter into delaying tactics and other methods in the hope of securing some kind of win for their “clients.” The trial will afford Mohammed the opportunity to grandstand and make use of his time in front of the world media to rally his disgusting terrorist cohorts. It will also be an insult to the victims of 9/11, as Mohammed will no doubt use the opportunity to spew his hateful rhetoric in the same neighborhood in which he ruthlessly cut down the lives of so many Americans. [...]
If we are stuck with this terrible Obama Administration decision, I, like most Americans, hope that Mohammed and his co-conspirators are convicted. Hang ‘em high.