>>>President Barack Obama says confirmation that Syria used chemical weapons would cause the United States to rethink its military options in connection with the two-year old civil war there.  But domestic political pressures make it unlikely that President Obama would deploy U.S. ground forces as one of his military options.

As civil war continues to rage in Syria, the Obama administration is trying to confirm its belief that the Syrian government has used chemical weapons against its own people.

President Obama has repeatedly said that would be a game changer.

“That would be an escalation in our view of the threat to the security of the international community, our allies and the United States and that means that there are some options that we might not otherwise exercise that we would strongly consider," said President Obama.

Some Republicans believe there is enough evidence for the U.S. to act more aggressively in Syria, either by arming the rebels or establishing a no-fly zone.

Senator John McCain spoke about a recent visit with Syrian refugees on NBC’s Meet the Press.

“This woman who was a school teacher said: 'Senator McCain, you see these children here?  They are going to take revenge on those people who refuse to help them.' They are angry and bitter and that legacy could last for a long time too unless we assist them," said McCain.

But even McCain opposes the deployment of U.S. ground troops, and analysts like Michael O’Hanlon of the Brookings Institution agree.

“I think the administration will be obliged to do something, or at least that is should feel obliged to do something," said O’Hanlon. "But that does not mean that we should put 75,000 Americans on the ground in Syria because of one small, limited chemical weapons use.”

Public opinion polls suggest little interest among Americans to get deeply involved in Syria, a view tourists visiting Washington seemed to confirm.

“You know, we can’t control the world and it needs to have a really, really good reason to go in there," said one.

“I think there probably is a little fatigue on putting our troops out there.  Of course there is a price to be paid for freedom and I think that we take that mantle on frequently," said another.

Americans have lost patience with foreign military involvements after lengthy wars in Afghanistan and Iraq, says Carroll Doherty of the Pew Research Center.

“I mean the public is just glad to be out," said Doherty. "They are divided over whether it was right or not and you still see the same partisan divisions.  But there is just a sense of fatigue with these struggles, even Afghanistan where troops still are.”

But those who argue for a stronger U.S. role in Syria remain hopeful the Obama administration will respond to what they see is a humanitarian crisis there.

Jim Arkedis is with the Progressive Policy Institute:

“As the Obama team shapes its legacy on foreign policy, there are ways to be active in the international community without necessarily sending troops and my hope is that they get to a point where they are more aggressive in promoting America’s role abroad," said Arkedis.

The latest CBS News/New York Times poll found that only 24 percent of Americans believe the U.S. has a responsibility to intervene in Syria, while 62 percent oppose the idea.