Unlike the vote in the British Parliament on Aug 29, which rejected Prime Minister David Cameron's proposal for airstrikes against Syria, there were signs at the US Senate Foreign Relations Committee hearing on Tuesday that US President Barack Obama may get a green light from lawmakers.

The committee will consider a revised resolution on Wednesday that authorizes military action against the Syrian government but rules out any commitment of ground forces. The new resolution will also restrict the military strikes to 60 days. Obama can extend it by another 30 days, if he notifies Congress and if Congress does not object.

Obama decided to take the issue to Congress on Saturday in the face of criticism over his planned attack. His original resolution has now been narrowed in scope, and it gained support from key members of the Senate from both parties, as Secretary of State John Kerry, Defense Secretary Chuck Hagel and Chairman of the Joint Chiefs of Staff Martin Dempsey made their case on Tuesday.

Doubts, however, still abound among lawmakers and a public wary of further wars such as those in Iraq and Afghanistan.

While approval from the Democrat-controlled Senate is likely, the outcome from the House of Representatives, where Republicans hold the majority, seems uncertain after members return from summer recess in the coming two weeks.

Senator Rand Paul, a Republican from Kentucky and the most vocal opponent of military action, said on Tuesday that he would not rule out the possibility of launching a filibuster over the issue in the Senate.

He said he believes that an attack on Syria would create more turbulence and danger in the region, and may not even disable the Syrian government's ability to launch chemical attacks.

Public opposition in the US was on the rise over the Labor Day weekend, which saw protests in many cities, including Washington, just outside the White House.

The Senate committee hearing on Tuesday was interrupted by protesters, including anti-war activist Medea Benjamin, who shouted, "Nobody wants this war!" before she was forced out of the room.

A Pew Center poll released on Tuesday showed that 48 percent of US citizens oppose military airstrikes against Syria in response to alleged chemical weapons attacks that the White House blames on Syria. Twenty-nine percent support the proposed airstrikes.

The poll found that 75 percent believe that US airstrikes in Syria are likely to create a backlash against the US and its allies in the region, and 61 percent think it would be likely to lead to a long-term US military commitment there.

Meanwhile, only 33 percent believe airstrikes are likely to be effective in discouraging the purported use of chemical weapons, and roughly half think they are not likely to achieve the goal.

Many people in the US are haunted by the idea that the US may be fighting on the same side as some extremist groups, including al-Qaida, in opposing the Syrian government. Some have questioned the double standard that previous administrations have adopted, given that the US did not respond after Saddam Hussein killed many more people with nerve gas in the 1980s. The Iraqi president was a US ally at that time.