Protesters hold up their red-painted hands behind Secretary of State John Kerry as he testifies on Capitol Hill in Washington, September 4, 2013, before the House Foreign Affairs Committee hearing on Syria. (AP Photo/ J. Scott Applewhite)   Among the many questions the Obama administration has been unable or unwilling to answer regarding its plans for military strikes in Syria is what happens if Congress refuses to authorize the use of force.

It’s a question that should be answered before, not after, a vote occurs in Congress, because it will clarify whether lawmakers are now engaged in the binding decision-making process required by the Constitution, or whether they are merely being used to lend an air of domestic legitimacy to military action that would violate international law.

Senator Rand Paul made the point yesterday near the end of the hearing before the Senate Foreign Relations committee, which heard testimony from John Kerry, Director of Defense Chuck Hagel and Chairman of the Joint Chiefs of Staff Martin Dempsey. Paul asked Kerry whether the president would abide by Congress’ vote. “I don’t know what the president’s decision is,” Kerry answered, “but I’ll tell you this …he still has the constitutional authority and he would be in keeping with the Constitution.”

Paul objected: “If we do not say that the Constitution applies, if we do not say explicitly that we will abide by this vote, you’re making a joke of us. You’re making us into theater, and so we play constitutional theater for the president. If this is real, you will abide by the verdict of Congress. You’re probably going to win. Just go ahead and say it’s real, and let’s have a real debate in this country and not a meaningless debate that in the end you lose and say, ‘Oh well, we had the authority anyway, we’re going to go ahead and go to war anyway.’ ”

Putting his face in his hand, Kerry said, “Senator, I assure you there is nothing meaningless and there is everything real about what is happening here.”

Paul interrupted, “Only if you adhere to what we vote on, only if our vote makes a difference, only if our vote is binding is it meaningful.”

Since President Obama announced his decision to request authorization from Congress, the message coming from the administration has been that Congress’s vote, while important politically, is essentially insignificant from a legal perspective. House Minority Leader Nancy Pelosi made that distinction yesterday after a meeting at the White House. “I don’t think congressional authorization is necessary, but I do think it is a good thing, and I think we can achieve it,” she said.

Moreover, Pelosi argued that there is precedent for a chief executive to proceed with military strikes even after they have failed to achieve congressional authorization. “In 1999, President Clinton brought us all together, similar to this meeting here…to talk about going into the Balkans and the vote was 213-213 [in the House],” Pelosi recounted. “He went. And you know what happened there.”

Contrary to the administration’s position, constitutional scholars argue that the president has no authority to initiate airstrikes without the approval of Congress, and that there is in fact no precedent for doing so in defiance of a clear rejection by Congress of a request for authorization. “The president does not have authority under the Constitution to launch a military attack on another country absent an emergency created by the imminent threat of an armed attack on the United States. So, whatever his claim, the reality is that what he is doing is constitutionally required,” said Michael Glennon, a professor of international law at Tufts University’s Fletcher School of Law and Diplomacy. “The constitutional case against presidential power would be strengthened even further by a rejection of authorization.”

Glennon said that there is “virtually no precedent” for the chief executive to proceed in the face of explicit congressional opposition, even considering Pelosi’s historical example. In 1999, Clinton ordered the military to engage Serbia the day after the Senate voted to authorize strikes, and before the House vote ended in a draw. While several presidents initiated strikes prior to seeking congressional approval, Glennon noted that very few of these instances were significant uses of force against significant adversaries that created significant risk.

How great the use of force will be is a matter of debate, but clearly the risks of military action in Syria are great. Without Security Council authorization or a legitimate claim of self-defense, said Glennon, under the UN Charter Syria would have the right to defend itself by force, and to call upon its allies—namely, Russia and Iran—to come to its defense.

As for the War Powers Resolution of 1973, Glennon said it was a wide misunderstanding that the Resolution authorizes the use of force for a sixty-day period. “The War Powers Resolution itself makes clear, in section 8A, that nothing in the resolution may be construed as conferring any power on the president which he would not have had in its absence,” said Glennon. “If Congress does nothing, the War Powers Resolution cannot be relied upon by the executive as conferring authorization. And if Congress says no, the president’s power is doubly undercut.”

Louis Fisher, a scholar-in-residence at the Constitution Project and a specialist on the separation of powers, agreed that if Congress votes not to authorize the use of force, proceeding with airstrikes would be an unprecedented violation of the Constitution. But Fisher is also concerned by what he called “the incredible abdication of congressional authority” expressed in the joint resolution presented by the Senate Foreign Relations Committee for markup this morning.

The last of twelve “whereas” clauses in the resolution states that “the President has authority under the Constitution to use force in order to defend the national security interests of the United States.” Fisher said he’s never seen language that broad, and that the resolution’s authors are acknowledging presidential authority that has in fact never been granted by the Constitution. “The expectation of the framers of the Constitution was that when one branch’s rights were encroached on, it would fight it off. Congress has failed to do that,” said Fisher.

In the past, chief executives have predominantly used international rather than constitutional law to justify unauthorized acts of war, namely by referencing their duty to uphold the UN charter. President Truman’s administration argued that maintaining the effectiveness of the UN was “a paramount United States interest” in an opinion regarding engagement in Korea in 1950, and the George H. W. Bush drew on that language to support the use of force in Somalia.

Most recently, after the UN authorized the use of force to protect civilians and instituted a no-fly zone in Libya, the Office of Legal Council cited the “U.S. commitment to maintaining the credibility of the United Nations Security Council and the effectiveness of its actions” in an opinion providing legal justification for Obama’s engagement in Libya, for which he did not initially have congressional authority.

Initiating airstrikes in Syria would undermine rather than uphold the credibility of the UN Charter, which generally permits the use of non-defensive force only with Security Council authorization. That has not been granted. The charter’s purpose is in fact to prevent individual states from engaging in the sort of international policing the US is proposing to undertake in Syria. Ultimately, it isn’t clear where the administration could turn for legal justification in the event of a no vote in Congress.

Even without a strong legal foundation, if the administration decides to proceed with airstrikes, there isn’t much Congress could do to stop it. Beyond impeaching the president or denying funds, both of which would require an unlikely stiffening of spines, Congress could hold hearings, as Senator William Fulbright and the Foreign Relations Committee did in the late 1960s and early ’70s concerning the war in Vietnam. It was at one of those hearings that a 27-year-old Naval lieutenant named John Kerry gave his first congressional testimony, against that ill-begotten war.

In Glennon’s view, it would be “almost unthinkable” in political terms for the president to proceed to attack Syria following the rejection of authorization by Congress. The administration wouldn’t be working so hard to make sure authorization passes if it didn’t recognize that fact. Rand Paul said this morning that he planned to introduce an amendment that would reaffirm Congress’ constitutional authority and the binding nature of its vote, and there are many others in Congress whose calls for authorization last week expressed a similar understanding of the Constitution. The only reason to object to such an amendment is to give the president an escape hatch by which to evade the outcome of the debate. If he has that—what’s the point?

The editors explain why a bipartisan coalition in Congress must turn Obama down.

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