prisoners of an abstract war

The media's currently hyperventilating over the fine line between the executive and legislative branches of government. The question is this: Can the executive branch take prisoner an American citizen and deprive him of all legal rights? We're speaking specifically of such things as representation by attorney, of fair trial by a neutral party, of - basically - the assumption of innocence until guilt is proven.

( Cut for excessive political ranting and dubious legal reasoning. )