3. We will NOT obey any order to detain American citizens as “unlawful enemy combatants” or to subject them to trial by military tribunal.
One of the causes of the American Revolution was the denial of the right to jury trial, the use of admiralty courts (military tribunals) instead, and the application of the laws of war to the colonists. After that experience, and being well aware of the infamous Star Chamber in English history, the Founders ensured that the international laws of war would apply only to foreign enemies, not to the American people. Thus, the Article III Treason Clause establishes the only constitutional form of trial for an American, not serving in the military, who is accused of making war on his own nation. Such a trial for treason must be before a civilian jury, not a tribunal.
The international laws of war do not trump our Bill of Rights. We reject as illegitimate any such claimed power, as did the Supreme Court in Ex Parte Milligan (1865). Any attempt to apply the laws of war to American civilians, under any pretext, such as against domestic “militia” groups the government brands “domestic terrorists,” is an act of war and an act of treason.
Now, I'm pretty much a libertarian, so I support most of the things that libertarians are in favor of, but there is always the wacky little bit that I just can't go in for and each little libertarian group seems to have its own wacky bit. So, although I used to be a card-carrying LP member, I no longer am because I don't support ridiculousness such as abortion-on-demand, open borders, and isolationism abroad.
The problem with Oathkeepers' #3 above is that if I took that seriously it means that I can't participate in warfare against anyone who happens to be an American citizen regardless of their ideology. So if Osama bin Laden happened to possess US citizenship while doing what he did on 9/11 this group would want him arrested in the mountains of Afghanistan with a warrant, etc. by proper police forces.
Screw that, if someone attacks us in a way that is unlawful under the international laws of war then I'm perfectly willing to have them be defined as an "unlawful enemy combatant" regardless of their citizenship and shoot them on sight. Assymetrical warfare ain't beanbag and libertarians should stop pretending that it is.