I would not have voted for the Military Commissions Act in the form that it passed Congress. One of the problems with the law of the war on terror is that we can't really frame it as exactly like war or exactly like law enforcement. There are ways in which it is like both and we need to develop a hybrid legal regime in response. In attempting to do this, I think the administration has, from time to time, missed the mark.
But here in Wisconsin's political blogosphere, I have noted that a few of our friends on the left side of the virtual divide have repeated the claim that the Military Commissions Act repeals habeas for citizens and non-citizens alike.
Lots of people on the left say this, but it is untrue. In fact, it is not even arguably true. The MCA does have an extremely broad definition of "unlawful enemy combatant" that could be applied to citizens. I don't like that definition at all.
But ... the definition is adopted for the purposes of the Act and the Act provides for trial by military commission and the suspension of habeas for "alien enemy combatants." In other words, the Act limits these operative provisions to people who are both unlawful enemy combatants and aliens. The commission and habeas stripping provisions quite clearly do not apply to citizens.
Some people have argued that a President might use the definition of unlawful enemy combatant in a number of unsavory ways and I suppose that he or she might. But nothing in the Act empowers him or her to do so. The definition, while overly broad, by its terms applies only to the newly created Chapter 47A which provides for military commissions and strips habeas for alien enemy combatants.