Wait, what's wrong with making sure people who's only goal in life is to kill as many people as possible in the most gruesome way they can think off don't get the chance to rejoin their comrades and do exactly that?
Prove that that is the case with each and every suspect held at Gitmo. These suspects in some cases had no probable cause; All that happened is some villagers turned them in for the no-questions-asked $1000 reward.
On a different level; consider what would happen if someone accused you of being a terrorist. You would be captured, throw in jail, and then kept there for a decade. No trial, no attempt to prove your guilt.
As long as it is possible to hold ANYONE in specific, for ANY reason, without due process, it can happen to ANYONE in general.
The men in Gitmo are most likely bad men; more than likely there is plenty of evidence of this fact. There is no risk of them ever failing to be convicted. All I want is for them to be convicted so they can be correctly treated as convicts.
Then there's the torture. The US used to be able to say "We do not torture." We might have roughed up some nazis, or maybe been a little harsh with a few suspects, but the policy was, No Torture. This was a good policy; generally, torture does not work; the only thing it does is get the subject to say what the torturer wants them to say. If that is "I did it", then that is what the subject will say. Every subject will eventually confess. Torturers continue until they get a confession.
Torture is only good as entertainment for sadists, not getting information.