The most basic foundation of our democratic experiment is that the government's legitimacy is grounded in its recognition of fundamental, inalienable human rights. Our Constitution guarantees these rights may not be abrogated by the state. A "prolonged" or "preventive" detention system creates or runs the danger of creating two categories of persons: those who have such fundamental rights and those who do not. This alters the entire dynamic of our system of government, as it means that those rights are not inalienable, but in fact, alienable; that the government has shifted from guaranteeing such rights to granting them. This puts us on the path of having our rights be a matter of fiat.
It is thus why creating a system of indefinite system, which parallels our legal system and thus circumvents and subverts it, in which a war on an abstract concept ("terror") is used to justify designating persons a threat to the "homeland" and putting them in prison is such a bad idea and a dangerous precedent. The whole idea is, putting it kindly, Kafka-esque; the inability to convict someone in a court is the justification for putting them in prison based on the potential that they might commit a crime. Not putting it kindly, this is the sort of reasoning that Hannah Arendt identified as totalitarian logic.
Speaking about the warrantless NSA surveillance program Skitolsky explains how Vice President Cheney's contention that the program helps "prevent possible terrorist attacks" is circular totalitarian logic that justifies the program on the grounds that it might prevent a possible attack. She also notes that "in a world where 'all is possible,' facts take a backseat to possibilities, and, since every citizen is a possible terrorist, then every citizen is a possible threat and so also a possible detainee."Preventive detention is an attempt at the impossible, an attempt to eliminate the possibility of crime, of uncertainty. As the philosopher Michael Oakeshott put it, "to try to do something which is inherently impossible is always a corrupting enterprise."
The possibility than any citizen might be a terrorist provides the rationale for making every citizen the target of surveillance. And since the world is full of possible, if not actual, threats, preemptive war threatens to turn into perpetual war, perpetually justifying the police state powers claimed by the administration.
Requoting Robert Bolt's A Man for all Seasons
Wife: Arrest him!
More: For what?
Wife: He's dangerous!
Roper: For all we know he's a spy!
Daughter: Father, that man's bad!
More: There's no law against that!
Roper: There is, God's law!
More: Then let God arrest him!
Wife: While you talk he's gone!
More: And go he should, if he were the Devil himself, until he broke the law!
Roper: So, now you give the Devil the benefit of law!
More: Yes! What would you do? Cut a great road through the law to get after the Devil?
Roper: Yes, I'd cut down every law in England to do that!
More: Oh? And when the last law was down, and the Devil turned 'round on you, where would you hide, Roper, the laws all being flat? This country is planted thick with laws, from coast to coast, Man's laws, not God's! And if you cut them down - and you're just the man to do it - do you really think you could stand upright in the winds that would blow then? Yes, I'd give the Devil benefit of law, for my own safety's sake!