"The Taliban refused to give them up. That is justification enough."

*Maybe* they didn't want to admit they didn't have the power to give them up. And we didn't even recognize the Taliban govt, who's to say the Taliban govt recognized the US govt (it's a two street, you know). And how can you request something from a govt that does not exist?
There could lots of arguments a lawyer could make if they examined the issue not to mention all the "confusion" of history with the Soviet invasion and US supporting "terrorists" which by the way included Bin Laden: etc & etc

"Lawyers in the Pentagon? I have no doubt of it. However, the military lawyers are there to administer military law, not to second-guess or countermand the orders of the Commander-in-Chief and his duly appointed deputies."

Ever heard of the Geneva Convention?

"That challenge would be the job of the C-in-C's boss: We the People. I, for one, don't intend to be cowed into silence because I don't know as much as the Pentagon's lawyers. I daresay there are a few things I know better than they. If there's something I ought to know in order to do my job as an American (which is not to bow to authority, but to question it), then it's their job to let me know what it is. "The President says so" is insufficient."

Well, I didn't mean for you to do any cowing, I just thought you should add this into how you approach the question [it's not JUST a bunch of stupid Right Wingers who drool over idea of seeing poor women & children being slaughtered].
And yes, the Supreme Authority (as far as I'm concerned) comes from the People. It is because of this fact that the President and Congress who represent the will of the people has it's authority (of, by, for, the People). [Whereas the constitution is a higher authority over the govt, it's not a higher authority over the People- and since the Supreme Court follows the constitution it does not have a higher authority over the constitution or the People. Therefore it silly for supreme court to decide that any treaty has higher Authority than Congress or President- they "take their orders from the higher authority".]

"I'm not sure where the cruise missles vs. troops on the ground argument came from. I don't recall differentiating or saying that one was superior to the other."

Well you said this lastest warfare against Iraq was pre-emptive. Which I assume you are referring to *starting* a war. Was Clinton use of cruise missiles a pre-emptive war? And if Clinton had started a war when was this particular war over? How is there any legal difference in defining a war in which there is difference between cruise missiles or using the army to capture and hold ground. Other than you have some bias for the navy-airforce over army-marines:)

"Also, the last I heard, we weren't at war, legally. That requires a declaration of war by Congress. This is an executive action that looks and behaves like war in every way but is not, legally. That circumvention of a Constitutional requirement also bothers me a lot. Furthermore, it might explain all those lawyers."

Well, from the commander-in-cheif prospective, he is charged with the duty of defending the nation. If you provide the commmander with a large miltary, then he is going to use it as best as he/she can. So if the Congress wants to limit President [miltary] power they need only refuse to fund a large miltary. I don't think in theory the Framers wanted the US to have a large standing army- though WWII certainly did a lot to change that idea. Though as I recall from beginning, Jefferson wanted a navy (gun boats for coastal defense) at least once he got in office, that is:)
Look, I'm been against the idea of having a large miltary for long time- not just because it costs money, but also it "allows" Presidents to use this miltary power, but I'm not against using this power if it is made available; it then become a question of using this power wisely. Doesn't make much sense to have some huge expensive miltary and at same time not be willing to use it- which is exactly why I'm against a large miltary- plus it gives a false sense of security.
I could live with miltary budget about 1/2 the current one- even less 1/2 the number of soldiers but more mobile and effective. Of course, that would be political suicide [esp for a Democrat] and generally speaking bureaucrats hate to shrink their workforce [it marks them as *failing*:].