Read the first paragraph of the article closely:
President Obama told human rights advocates at the White House on Wednesday that he was mulling the need for a “preventive detention” system that would establish a legal basis for the United States to incarcerate terrorism suspects who are deemed a threat to national security but cannot be tried, two participants in the private session said.
If the enabling act that permits him to do this is written as the journalist reports it in that paragraph, it does not state that this law would provide for preventive detention for enemy combatants captured overseas. Read it again: that would establish a legal basis for the United States to incarcerate terrorism suspects who are deemed a threat to national security but cannot be tried. That is a WHOLE lot more generic.
Who are terrorism suspects? According to DHS, both you and I, for the cause of posting on this site, are considered rightwing extremists (and thus could be classified as potential terrorists). There are those who make a little more radical comments on this site who could, using the definitions supplied by DHS, be considered to be threatening terrorism. (Motivation) If those same people could potentially be shown to have the capability (i.e., knowledge, supplies), then you have the two elements required to establish suspicion. You know what you need for capability? You don't need guns. You don't even need knives or spears. All you need is to be a property owner and have the normal yard care supplies on your property (a molotov cocktail can be made with gasoline; a bomb can be made out of fertilizer).
Am I paranoid? Sure. But just because a person is paranoid doesn't mean that they're not out to get him!
The difference between GITMO and this is that those who were imprisoned at GITMO were captured overseas and were kept overseas. Therefore, they never had constitutional rights. They were held in the status in which they were held due to the fact that the laws of armed conflict don't cover the particular situation; so they could just be shot as spies / saboteurs (my preferred solution, but they don't listen to me all the time), or given a structured process whereby their status could be determined and dealt with judicially -- all without them ever touching US soil.
This, on the other hand, as written above, would apply to anybody suspected by the administration...but whom the administration could not try. Who could the administration not try? (1) those individuals who would gain access to highly sensitive information as a result of a trial process, (2) those individuals who did not commit a crime triable in the US, (3) those individuals whose rights were not adequately protected during the arrest / pre-trial imprisonment processes, and (4) those individuals where there is insufficient evidence to convict in a court.
I'm glad you apparently trust the motives of the administration and the Congress (as well as trusting the Court's judgment), but I don't.
Well said.