If there is no case, no legal grounds that he broke any U.S. laws, then at best, deport him. To my knowledge, any terrorist action, or planning a terrorist act is a violation of some U.S. law...so it becomes a matter of the US system of law and order. (See Fred Thompson on info of how Law and Order works

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But locking him up without any chance at a fair trial, is something I would expect out of Iranians, or Mexican jails, or Israel, etc.
Not America, at least not the way we preach to the world how fair and just we are...
We handle terrorists the same way as we would handle a gang member or gang leader. If we have evidence they broke the law, if we can prove it in a court of law, we try to prosecute according to the rules of law.
Anything less is not really truly American in spirit or practice, it is the very beginning of a fascist state.
Bush always says they hate us for our freedom, which I think is BS, but part of our freedom and our principle is rule of law, and justice.
That needs to be applied as much as we can equally, and if we have no factual case, then deport him, at best, but holding him for years without due process in any manner is not right.
It is such a dangerous ground to approve of incarceration simply because we "think" he is a terrorist, but are unable to prove it.
We put mobsters in jail, and we find ways to get evidence on them and people to testify against them....so what is the problem?
If we could simply make this what it is, a law and order situation, then our justice system, following the law as they do their job, will be just fine.
Just think if Hillary go in, and she decided to incarcerate Rush Limfat or Man Coulter for being a terrorist...simply because she wanted to.
Hmmm....maybe not such a bad idea after all...
Quote from AAAintheBeltway:
Let's focus on this case. It poses a difficult constitutional question. On the one hand, it seems clear that we all should be worried about any President having the authority to arrest and detain people indefinitely just on the assertion that they were aiding a terrorist group. If prosecutors can be dead wrong about something pretty straightforward, like say whether a stripper was raped by a group of lacross players, they can certainly be wrong about interpreting ambiguous records on their PC and concluding they are terrorists.
On the other hand, it is a bit naive to say, charge them in civilian court and try them or let them go. Often such people will have been uncovered using methods of intelligence gathering that the government has a legitimate interest in keeping secret or which wouldn't pass muster in civilian court. Is it really good public policy to give terrorists the same rights as US citizens merely because they managed to get into the country? Doesn't that make them more rather than less dangerous? And what about US citizens who are also terrorists? How do we handle them?
There is Supreme Court precedent that terrorists in the country illegally can be tried by military courts and executed. That was what was done to a group of German sabotuers caught here during WW II. It could be argued that any foreign terrorist here legally had in fact committed visa fraud, since he would have denied being a terrorist and hence, he should be treated as being here illegally. Clearly that argument is a bit circular, as someone has to determine that he is in fact a terrorist.
Personally, I would be comfortable with reserving habeas corpus for citizens and lawful permanent residents and relegating others to military tribunals. If you are here on a visa, it's probably not a good idea to be doing things that make people suspect you of being a terrorist.