...The Reuters/Ipsos poll, taken August 19-23, found that 25 percent of Americans would support U.S. intervention if Syrian President Bashar al-Assad's forces used chemicals to attack civilians, while 46 percent would oppose it. That represented a decline in backing for U.S. action since August 13, when Reuters/Ipsos tracking polls found that 30.2 percent of Americans supported intervention in Syria if chemicals had been used, while 41.6 percent did not.

Taken together, the polls suggest that so far, the growing crisis in Syria, and the emotionally wrenching pictures from an alleged chemical attack in a Damascus suburb this week, may actually be hardening many Americans' resolve not to get involved in another conflict in the Middle East.

The results - and Reuters/Ipsos polling on the use-of-chemicals question since early June - suggest that if Obama decides to undertake military action against Assad's regime, he will do so in the face of steady opposition from an American public wary after more than a decade of war in Iraq and Afghanistan....