Six burning questions on Obama’s Syria decision

President Barack Obama walks with Vice President Joe Biden to the Rose Garden of the White House on Saturday to speak on the situation in Syria Mike Theiler / REUTERS

President Barack Obama's unexpected decision to seek approval from Congress before launching any military action against Syria surprised many of his own advisers as well as military analysts who predicted U.S. Navy ships were on the brink of firing missiles into areas around Damascus.

Obama explained the surprise move on Saturday afternoon, telling the nation: "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."

The president still noted that he believes he has "the authority to carry out this military action without specific congressional authorization." 

His decision raises a number of burning questions, ranging from impact the move has on the scope of presidential power to whether the president would decide to launch an attack on Syria if Congress eventually refuses to support military action after it returns Sept. 9.

Does Obama’s decision diminish the power of the presidency, both at home and abroad?

For the past 30 years, U.S. presidents have tried to ramp up the powers of the executive branch on national security issues. Presidents Ronald Reagan and Jimmy Carter, for example, exercised military might without a vote in Congress. Obama’s decision on Syria represents a clear reversal of that trend, observers say. And his deference to congressional lawmakers could create a political, and potentially legal, precedent that may cast a shadow over future administrations.

Obama also now runs the risk of losing the vote on authorization in Congress, leaving him with his hands tied despite previous pledges to intervene if Assad used chemical weapons.

Chuck Todd: Obama faces a tough fight in the House 4:14

Why did Obama have Secretary of State John Kerry make such a forceful case for an attack?

At the time Kerry made his passionate speech on Friday condemning the alleged chemical attack as a "crime against humanity" and calling Syrian President Bashar al-Assad a "thug and murderer," Obama was still leaning toward ordering a strike without congressional approval, senior officials told NBC News. 

Analysts say Kerry was blindsided by Obama's reversal later in the day. Even a perceived disconnect between Obama and Kerry among world leaders could hurt their credibility.

"Here's a guy (Kerry) who gave probably the most impassioned and effective speech of his entire career," said retired Col. Jack Jacobs, an NBC News military analyst. "It was convincing. And yet, the very next day, this guy gets his legs cut out from under him."

Do Obama and Kerry agree about Syria? 1:18

How do Obama's legal credentials come to play in the Syria crisis?

Obama, who graduated from Harvard Law School, was a senior lecturer at the University of Chicago for four years. In 2007, in an often-cited critique of then-President George W. Bush, Obama said: "I was a constitutional law professor, which means unlike the current president, I actually respect the Constitution."

Obama's decision on Syria was grounded in similar terms: He said he was "mindful that I'm the president of the world's oldest constitutional democracy." Administration officials said the legal basis for a potential strike against Syria had been a key part of every international discussion since the start of the debate over intervention.

A range of circumstances — the British parliament's vote against military involvement and the absence of U.N. Security Council authorization — made the legal questions more acute, officials said. And an NBC News poll released Friday morning showed that nearly 80 percent of Americans agreed that the president should seek approval in advance of taking military action.

Obama and his legal counsel, Kathy Ruemmler, had discussed pursuing congressional approval prior to the president's ultimate decision. Yet before Obama told key advisers Friday evening that he planned to go Congress for approval, his own National Security Council had believed that requiring a vote was not on the table, officials told NBC News. The National Security Council officials thought that “consultation” in the form of congressional briefings and behind-the-scenes conversation was all that would be needed before a strike. One senior official noted that no key leaders in Congress had specifically requested a vote on military intervention. 

When did Obama decide to seek congressional approval?

Senior White House officials told NBC News Chief White House Correspondent Chuck Todd that Obama made up his mind Friday evening while walking across the South Lawn with Chief of Staff Dennis McDonough.

While debate within the administration continued into late Friday, by Saturday morning the senior advisers acquiesced, the senior officials said.

Is Obama setting a precedent by delaying on Syria? 13:07

Is there a 'red line' anymore? Was there ever one?

On Aug. 20, 2012, Obama said: “We have been very clear to the Assad regime, but also to other players on the ground, that a red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized.

"That would change my calculus. That would change my equation," Obama said.

Many lawmakers have criticized the statement over the past several months and on Friday, Sen. John McCain, R-Ariz., said the red line “was written in disappearing ink,” adding that the failure of the United States to intervene in Syria’s civil war was “shameful.”

What will Obama do if Congress doesn't authorize military action?

White House officials say Obama feels military action is required in Syria and would still order a missile strike if Congress fails to approve military action. In his speech Saturday, Obama emphasized he believes he has the authority to move forward without congressional approval.

“Yet, 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,” Obama said. “We should have this debate, because the issues are too big for business as usual. And this morning, John Boehner, Harry Reid, Nancy Pelosi and Mitch McConnell agreed that this is the right thing to do for our democracy.”

Obama faces a tough path forward in the GOP-controlled House, where members have previously pushed for votes on resolutions that would have blocked funding for military operations in Syria or the arming of rebel groups in the war-torn country. 

And the House has recently been fractured on national security issues, with both parties split over how far the government should go in preventing terrorism at home and abroad.

With some members of Congress deeply skeptical of Obama’s claim that Assad’s reported use of chemical weapons could endanger U.S. national security, those same fissures are sure to emerge as the Congress – on behalf of a war-weary and deeply divided American public -- contemplates the use of force.

But Obama urged a measured reaction from lawmakers.

“To all members of Congress of both parties, I ask you to take this vote for our national security. I am looking forward to the debate,” he said. “And in doing so, I ask you, members of Congress, to consider that some things are more important than partisan differences or the politics of the moment.”

Congress is set to return to Washington, D.C., on Sept. 9. House Speaker John Boehner and other GOP leaders have said they expect to consider the Syria authorization that week. 

NBC News' David Gregory, Andrea Mitchell and Chuck Todd contributed to this report.