Twodees, before you strike you should read. The Constitution specifies that the "priviledge of the writ of habeas corpus" can be suspended. The poster did find it. It's in the Constitution.
The priviledge of the writ of Habeus Corpus shall not be suspended, unless in time of rebellion or invasion the public safety may require it.
It's a power only of congress. It becomes a presidential power in Congress's absence but it does require their later approval unless their approval was given in advance.
W operates under the general permission given to him by congress to deal with wartime threats, but this is another reason the matter will come back again to haunt W as election politics become increasingly involved. The current benefits of a few needlessly rigged trials may not be worth the endless spin on the violations of rights that will eventually come out as most of the detainee's are let go. This was also a great problem for Lincoln, and as we see her today all these years later, it still is a problem for his reputation.