With a surprise twist on a holiday weekend in the United States, president Barack Obama announced that he would seek a vote in the U.S. Congress prior to launching a missile strike on Syria in retribution for last Wednesday’s chemical attack on the outskirts of Damascus.

Coming in the wake British prime minister David Cameron’s humiliating defeat over a resolution in the House of Commons authorizing the possibility of British force late last week, Obama argued that, while he has already made a decision to punish Syrian president Bashar al-Assad for the chemical attacks in his capacity as commander-in-chief of the U.S. armed forces, he has also decided to seek authorization for use of force from Congress:

Having made my decision as Commander-in-Chief based on what I am convinced is our national security interests, I’m also mindful that I’m the President of the world’s oldest constitutional democracy.  I’ve long believed that our power is rooted not just in our military might, but in our example as a government of the people, by the people, and for the people.

Obama’s surprise announcement postpones any US action until at least the week of September 9 — well after chemical weapons inspectors from the United Nations will report back next week about the nature of the attack and well after next week’s G20 meeting in St. Petersburg, Russia, where president Vladimir Putin, an Assad ally, has repeatedly blocked action against Assad (a Russian ally) by the UN Security Council and earlier today, called the possibility of US and Western punitive strikes ‘utter nonsense.’

While Obama’s decision will hearten critics on both the American left and right who have called for a greater legislative role on the Syria question, it’s unlikely to satisfy hawkish critics like U.S. senator John McCain of Arizona who has pushed Obama toward supporting regime change in Syria, and it’s also unlikely to satisfy dovish critics who believe there’s no U.S. national interest in launching military strikes on the Assad regime.  It will also leave multilateralist critics dissatisfied, given that Obama stated clearly that he was willing to act without the backing of what he called a ‘paralyzed’ Security Council.

But it’s also an unexpected position for an administration that pushed the boundaries of the 1973 War Powers Resolution just two years ago when it ordered military action in Libya.  At first glance, Obama’s 2011 decision to support the UN-authorized, NATO-enforced effort to establish a no-fly zone and to arm rebels fighting against Libya’s late strongman Muammar Gaddafi without congressional authorization arguably violated his constitutional obligation to Congress, while a limited military strike on Syria lasting just a few days to a few weeks would not require congressional approval under any view of the War Powers Resolution.

So what gives?  How can the Obama administration reconcile its position on Libya with its newfound enthusiasm for Congress on the Syrian question?  The answer could transform the nature of U.S. foreign policy and the ability of the U.S. president to act decisively in the future.

Enacted in 1973 during the twilight of the U.S. military debacle in Vietnam by Congress and overriding a veto from then-president Richard M. Nixon, the War Powers Resolution purports to require that any U.S. president notify Congress within 48 hours of committing armed forces to military action and to forbid a president from committing forces for more than 60 days (or 90 days, including a period of withdrawal) without congressional authorization.

Every president since Nixon has taken the position that the War Powers Resolution unconstitutionally infringes on executive power, but none has ever challenged the statute in court on the obvious worry that the courts might not find it unconstitutional, but instead a valid check on executive overreach.  Ronald Reagan launched a military invasion of the Caribbean island nation of Grenada in 1983 and a peacekeeping force in the same year in Lebanon, while Bill Clinton joined the NATO efforts to end ethnic cleansing in Kosovo in 1999, in each case without bothering with congressional authorization.  For its part, Congress has never forcefully punished the executive branch for sidestepping the requirements of the War Powers Resolution.  In the wake of Obama’s decision to intervene in Libya, the House of Representatives supported a largely symbolic resolution opposing the use of US force in Libya just an hour before it also refused to withdraw funding for the Libya effort.

Much of the confusion stems from the ambiguity of the US constitution on federal war-making powers, which anoints the president as commander-in-chief and the chief US representative on foreign affairs, yet also gives Congress the power to declare war and the financial power to fund wars.

Two years ago, the Obama administration argued that the military action in Libya didn’t rise to the level of full-blown ‘hostilities,’ and so the War Powers Resolution wasn’t applicable.  At the time, White House attorneys argued that they didn’t need congressional approval because the level of U.S. involvement in Libya didn’t constitute full-blown ‘hostilities,’ the threshold that has to be reached to trigger the 1973 War Powers Resolution:

In our view, determining whether a particular planned engagement constitutes a ‘war’ for constitutional purposes instead requires a fact-specific assessment of the ‘anticipated nature, scope, and duration’ of the planned military operations.  This standard generally will be satisfied only by prolonged and substantial military engagements, typically involving exposure of U.S. military personnel to significant risk over a substantial period.

The Obama administration also argued at the time that the Libyan effort would put no U.S. soldiers in harm’s way and that the action would be limited to supporting an existing UN resolution.

Despite long U.S. military action in Korea, Vietnam, Iraq, Afghanistan and elsewhere in the past 70 years, Congress hasn’t formally issued a declaration of war since the beginning of World War II in December 1941.

While the Obama administration’s legal rationale on the Libyan conflict met with considerable criticism, it was not necessarily inconsistent with past presidential practice in bypassing Congress.  But if the Obama administration’s constitutional case on Libya was doubtful, its case on Syria was always much stronger.  If Libya was permissible under the War Powers Resolution without congressional approval, certainly short-duration missile strikes against the Syrian regime wouldn’t require it.  The cynical view is that the Obama administration, suddenly stripped by the House of Commons of military support from its key British ally, wants the additional democratic legitimacy of the U.S. Congress to share the risk of what would be a unilateral strike.

But the less cynical view is that Obama is calling the vote as a matter of best democratic practices, and in calling for the vote, he forcefully argued that he wasn’t establishing a new precedent.  Even before announcing that he would seek congressional authorization, Obama stated that he had already decided that the United States should take military action against Syrian regime targets.  Moreover, he made it clear that he believed that he had the power to act even without Congress’s support:

While I believe I have the authority to carry out this military action without specific congressional authorization, I know that the country will be stronger if we take this course, and our actions will be even more effective.  We should have this debate, because the issues are too big for business as usual.

But what happens if Congress opposes Obama’s resolution on Syria?  It’s tempting to believe that the Obama administration, which made its decision in consultation with House speaker John Boehner, Democratic House leader Nancy Pelosi, Senate majority leader Harry Reid and Senate minority leader Mitch McConnell, would not push for a congressional vote without assurance that it will succeed.  But with Congress not scheduled to reconvene until September 9, there’s a lot of time for opinions to change on Capitol Hill.  Given that then-senator Hillary Clinton’s 2003 vote to authorize U.S. military action in Iraq arguably cost her the Democratic Party’s presidential nomination in 2008, potential 2016 presidential contenders will be very hesitant to support a military action that many U.S. voters oppose.

Would the Obama administration launch military strikes on Syria even if it loses the vote?  If so, why even bother with the political theater at all?  If not, would it mark a historic retreat in the struggle between the executive and legislative branches of government over foreign policy?  It’s unclear at this point, but the British example is instructive.  Under British legal precedent, the prime minister is generally believed to have a ‘royal prerogative’ to launch military action — the precedent to seek parliamentary approval is only a recent one, beginning with former prime minister Tony Blair’s decision to ask for the support of the House of Commons in advance of the 2003 invasion of Iraq.  So Cameron didn’t technically need to seek parliamentary approval over Syria, and he also could have proceeded with the use of force even after his defeat in the House of Commons, though he agreed immediately after losing the Syria vote that he would not override parliamentary will.

Photo credit to Josh Lederman / Facebook.