WASHINGTON- The Obama administration tried to bolster its case Tuesday for possible military action against Syria within days, with intelligence agencies preparing to release intercepted communications aimed at proving Bashar Assad perpetrated a large-scale chemical weapons attack on civilians. "There's no doubt who is responsible for this heinous use of chemical weapons in Syria: the Syrian regime," Vice President Joe Biden said.
The U.S. and international partners were unlikely to undertake military action before Thursday. That's when British Prime Minister David Cameron will convene an emergency meeting of Parliament where lawmakers are expected to vote on a motion clearing the way for a British response to the alleged chemical weapons attack.
Administration officials argued that Assad's actions posed a direct threat to U.S. national security, providing President Barack Obama with a potential legal justification for launching a strike without authorization from the United Nations or Congress. However, officials did not detail how the U.S. was directly threatened by an attack contained within Syria's borders. Nor did they present concrete proof that Assad was responsible.
In this Thursday photo, a Syrian shopkeeper waits for customers at the popular Hamidiyeh old market in Damascus. The veneer of normalcy is thin in Damascus, the stronghold of President Bashar Assad's rule, after more than 2 1/2 years of bloodshed.
"Allowing the use of chemical weapons on a significant scale to take place without a response would present a significant challenge to, threat to the United States' national security," White House spokesman Jay Carney said.
Assad has denied using chemical weapons, calling the allegations "preposterous."
Obama is weighing a response focused narrowly on punishing Assad for violating international agreements that ban the use of chemical weapons, an act the president repeatedly has said would cross a "red line." Officials said the goal was not to drive the Syrian leader from power or impact the broader trajectory of Syria's bloody civil war, which is now in its third year.
BY THE NUMBERS: Most not in favor of attack
As the U.S. weighs a response to Syria, recent polling has shown Americans largely opposed to military action and few paying close attention to the ongoing conflict. But that could change with the Syrian government's use of what the Obama administration says were chemical weapons.
No polling has been conducted on the public's views of Syria since that government was accused of using chemical weapons. But the trend lines against military action have been clear:
- Seventy percent told Pew Research Center pollsters in June that they opposed sending arms and military supplies to anti-government groups in Syria. That poll was conducted around the time the Obama administration announced it would be providing military aid to the anti-government forces.
- An NBC News/Wall Street Journal poll released earlier in June showed that two-thirds of Americans preferred that the U.S. provide only humanitarian assistance or take no action, compared with just a quarter who favored either providing arms or taking military action.
- A Gallup survey in May found 68 percent thought the U.S. should not intervene militarily to end the conflict should economic and diplomatic efforts to end it fail.
Even with that consensus, a Washington Post/ABC News poll in December suggested that the government's use of chemical weapons against its own people could change public opinion. In that poll, just 17 percent thought the U.S. military should get involved in the conflict as it was at the time, but 63 percent said they would support military intervention if the Syrian government used chemical weapons against its people.
The Pew Research Center has tracked public attention to news about the conflict in Syria since May 2011, and has consistently found most Americans are tuned out. Each time they've asked, a majority said they were not following closely.
So far, few have said they think the U.S. has a responsibility to intervene in Syria. A June CBS News/New York Times poll found just 28 percent said the U.S. had a responsibility to do something about the fighting in Syria, while 61 percent said it did not.
While the fighting in Syria has stretched on and escalated, Americans' views on the U.S. duty to act have changed little. Several news organizations have asked the same question about Syria, and a February 2012 CNN/ORC International poll was the first, finding just 25 percent thought the U.S. had a duty to act.
That sense of responsibility peaked in May 2012 at 33 percent.
Since the end of the Cold War, Americans have felt an obligation to get involved in just a few conflicts that did not directly involve the U.S. - about half said the nation had a duty to intervene in Somalia in 1993 and Darfur in the mid-2000s, and most said the U.S. had a responsibility to act in Kosovo in 1999.
The pattern with Syria is similar to the public's long-standing skepticism about U.S. involvement in the Bosnian war in the mid-1990s. CBS News and The New York Times tracked public opinion on the fighting between Serbs and Bosnians in the former Yugoslavia, and from 1993 through 1995, regardless of the intensity of the conflict, those who felt no responsibility to act outnumbered those who did.
"The options we are considering are not about regime change," Carney told reporters.
According to U.S. officials, the most likely operation would be largely sea-based, with the strikes coming primarily from Navy warships in the Mediterranean Sea. Fighter jets often are deployed to monitor the area and protect the ships, but Syria's robust air defense system makes air strikes more difficult and risky.
Defense Secretary Chuck Hagel said military forces stand ready to strike Syria immediately if the commander in chief gives the order. The Navy has four destroyers in the eastern Mediterranean within range of targets inside Syria and also has warplanes in the region.
"We are ready to go," Hagel said during a television interview while traveling in Asia.
Ahead of any strike, the U.S. also plans to release additional intelligence it says will directly link Assad to the Aug. 21 attack in the Damascus suburbs. Syrian activists say hundreds of people were killed in the attack. A U.S. official said the intelligence report is expected to include "signals intelligence" - information gathered from communications.
All of the officials insisted on anonymity because they were not authorized to publicly discuss the internal deliberations.
Even before releasing that information, U.S. officials said they had very little doubt that Assad was culpable in the attack based on witness reports, information on the number of victims and the symptoms of those killed or injured, and intelligence showing the Syrian government has not lost control of its chemical weapons stockpiles.