> There was no declaration of war, there was an authorization for the use of military force. Two very different things.

No, they aren't different Constitutionally at all. The AUMF is an exercise of the Constitutional power to declare war, which does not require any particular language to be used in exercising it, just as the Constitutional power to levy a tax depends only on whether the effect is a tax, not whether the Congressional action imposing the liability calls it a tax.

(It's possible that statutory provisions passed by Congress under its other powers may be conditioned on the specific language in a declaration, such that there may be different effects of something like the 9/11 or Iraq AUMF and something that explicitly uses language like "declares war", but that's a distinction caused by the exercise of other Congressional powers, not a Constitutional distinction that makes the former something other than an declaration of war from a Constitutional perspective.)

How exactly do you know that the AUMF-2001 invoked Congress' power to declare war rather than Congress' power "To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof."?

> How exactly do you know that the AUMF-2001 invoked Congress' power to declare war

Because its the only Constitutional power of Congress which could support it.

> rather than Congress' power "To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof."?

The necessary and proper clause isn't an independent alternative to other Constitutional powers, there still has to be a base Constitutional power to which the function is necessary and proper.

The base power needn't be a Congressional power given the section I highlighted. It could be an Article II power, such as the CinC power.

You've also overlooked the possibility that the AUMF is simply unconstitutional.

In any event, to end this sub thread, at least for my part, whether we are at war or not still doesn't answer the question because declaring war is not a carte blanche to ignore the rest of the constitution (see Hamdi v Rumsfeld). It in no way comports with war traditionally understood to assassinate personel vaguely associated with the enemy involved in the production of propaganda thousands of miles from any active battlefield. Nor is such a killing 'necessary and appropriate' in the words of the AUMF.

> The base power needn't be a Congressional power given the section I highlighted.

That doesn't change the answer. There's no other Constitutional power to which there is even a colorable argument that the AUMF is "necessary and proper" such that it would be supported independently of Congress power to declare war.

> It could be an Article II power, such as the CinC power.

It's doubtful that any such power exists -- the designation of the President as Commander-in-Chief of the military in Article II is a limitation on Congress' Article I power to regulate the military (specifically, it prevents it from dividing the roles that the founders saw as having an executive character by creating a separate C-in-C of the military, which its Article I powers would otherwise permit). But its not a power of government -- the designation of the President as CinC doesn't give the government any power that doesn't come from some other provision of the Constitution, it simply limits the manner in which other Constitutional powers may be exercised (it distributes some powers to the President to the extent that they already exist within the federal government, but for them to exist within the federal government, they must be grounded elsewhere in the Constitution.)

> In any event, to end this sub thread, at least for my part, whether we are at war or not still doesn't answer the question because declaring war is not a carte blanche to ignore the rest of the constitution

The answer was offered to the question of when did we declare war on the targets of these actions, and was not intended to say anything more about the Constitutionality -- and, even more so, appropriateness even if Constitutional -- of the actions, which is, I think, a much harder question that can't be answered without a thorough application of principles to the changing factual circumstances of technological means and realities of modern warfare.