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.