As Arne has pointed out, nobody in the House or Senate ever explicitly gave Bush the OK to invade Iraq--just to use his judgment. We have all learned--many knew before--that the good judgment of G W Bush is the ultimate oxymoron.

Digging back into my scholar days past, I'd say that Congress cannot -- consistent with the Constitution -- "g[i]ve Dubya the OK .. to use his judgement". There's a notion of "exclusive powers" and "nondelegability" in constitutional jurisprudence. Certain powers and responsibilities are given to one of the branches of gummint amd cannot be ceded or delegated to another branch, even if the branch given that original power is willing.

This shows up, for instance, in the legislative power: it is an exclusive power of Congress (as is the power to introduce spending bills, which is vested in the House of Representatives). Whie this "non-delegability" has been under erosion, court cases at least pay lip service to it in distinguishing between "legislation" and "regulation" when decididng if the executive has the authority to pass new rules. All "regulation" must be pursuant to corresponding "legislation" and a grant of regulatory authority, and if the "regulations" exceed the scope of the original legislation to the extent they become "new" legislation, they will be looked at askanse by the courts.

Certainly, in the instance of the power to declare war, there was a lot of discussion of why such power should not be vested in the executive, and why the deliberative bodies alone should be trusted with such an awesome and singular power, potentially affecting as it does in fact the very existence of the republic. I don't for a second doubt that the founders would be horrified at the thought that Congress would abdicate its role here and give to a president the decision as to whether to go to war. But that it did, and for that, Congress should be profoundly embarrassed ... and overturned.

Cheers,