Yesterday, Pres. Obama sent a request to Congress for an authorization to use military force against ISIS.
The sudden push for congressional authorization for war with ISIS seems a bit odd considering the president asserts he needs no such authorization, especially given the fact that the U.S. has engaged in military options against ISIS since this summer. 
From a constitutional standpoint, Obama usurped power with the first bombing run. The Constitution delegates the authority to declare war to Congress. As commander-in-chief, the president only has the authority to prosecute a war once declared. He does not have the power to initiate offensive military action. During the founding era, there was absolutely no debate about this. George Washington made this very point.
The Constitution vests the power of declaring war with Congress, therefore no offensive expedition of importance can be undertaken until after they have deliberated upon the subject, and authorized such a measure.
James Wilson was a proponent of national power, but even he acknowledged the strict separation of war powers during the Pennsylvania ratifying convention.
This system will not hurry us into war; it is calculated to guard against it. It will not be in the power of a single man, or a single body of men, to involve us in such distress; for the important power of declaring war is vested in the legislature at large: this declaration must be made with the concurrence of the House of Representatives: from this circumstance we may draw a certain conclusion that nothing but our interest can draw us into war.
So, setting aside the fact that Obama has engaged in a constitutional violation from the moment the first bomb fell on ISIS fighters, would the proposed authorization to use force remedy the constitutional issues?
No.
An open-ended authorization that gives the president wide latitude to determine where and when to engage an enemy does not serve as a substitute for a specific declaration of war.
Consider the wording of Obama’s proposed authorization.
The President is authorized, subject to the limitations in subsection (c), to use the Armed Forces of the United States as the President determines to be necessary and appropriate against ISIL or associated persons or forces.
By vesting in the president the authority to determine “necessary and appropriate” action, Congress would delegate its responsibility to the president. The resolution essentially gives the president a blank slate, with a few restrictions. It would even allow the president, at his discretion, to attack a sovereign nation.
The proposed AMUF not only undermines the intent of the Constitution regarding war powers, it also violates basic rules of construction.
When a principle (the people) delegates power to an agent (the federal government), that entity cannot transfer that power to another without specific direction. No such direction or authorization exists in the Constitution. So, Congress can’t simply give the president a blank slate to make a decision on war based on his own discretion. Congress must make that call, and make it specifically, before initiation of military action.
James Madison clearly laid out this principle.
The declaring of war is expressly made a legislative function. The judging of the obligations to make war, is admitted to be included as a legislative function. Whenever, then, a question occurs, whether war shall be declared, or whether public stipulations require it, the question necessarily belongs to the department to which those functions belong–and no other department can be in the execution of its proper functions, if it should undertake to decide such a question.
Pres. Obama flipped the constitutional process on its head. He’s made the decision to go to war, now he wants Congress to rubber-stamp it.
Historian Tom Woods summed up the constitutional responsibility of Congress when it comes to war brilliantly in an interview with Crisis Magazine.
The Congress will sometimes delegate to the president — unconstitutionally — its decision-making power to go to war. They say, in effect, “We authorize the president to make the decision. If and when he wants to go to war, he’ll have our approval.”
Well, you can’t know what the circumstances are going to be six months down the line. So it’s an easy way for Congress to absolve itself of blame if the thing goes haywire. What they need to do is have the old-fashioned declaration of war, because the Constitution is very clear on this. There are some areas where you might be able to make the case that it’s hard to know what the Framers meant. Not when it comes to war powers. You have an unbroken tradition going through the years prior to the Constitutional Convention: the Convention itself, the ratification debates, the Federalist Papers, and early national practice — all give the same testimony. It’s not even as if there’s a minority tradition that you can dig up arguing that the president could take the country to war. There’s nothing.
All the sources say, “We don’t want to live under a monarch anymore — someone who can take the country into unnecessary wars that harm the people’s interests. We want this to be a deliberative process by the branch of government closest to the people, namely, the Congress.”
That means that Congress alone can declare war.
