The U.S. role in the civil war in Syria has been limited to humanitarian aid and nonlethal equipment for the rebels. But that may change with recent revelations about the use of chemical weapons.
Polls show that Americans are still not paying close attention to the conflict, but there is a reluctance to intervene — a byproduct of the experience in Iraq.
President Obama says he's weighing all options. Whatever he decides, he'll have to make a case to the U.S. public.
There are voices in Washington trying to ratchet up the pressure on the White House to do more about Syria. Most prominent are U.S. Sens. Lindsey Graham, R-S.C., and John McCain, R-Ariz.
McCain said on NBC's Meet the Press this week: "We have said that they need a no-fly zone, which could be obtained without using U.S. manned aircraft. We could use ... Patriot batteries and cruise missiles to take out their air — and to supply the resistance with weapons."
But such calls are in the minority, and the White House is resisting them. Weeks ago, Obama warned Syria that the use of chemical weapons would cross a red line. Now that that line has apparently been crossed, the president's tone hasn't changed. He's signaling to the public that while new options may be on the table, deliberations are still underway.
"When I am making decisions about America's national security and the potential for taking additional action in response to chemical weapon use, I've got to make sure I've got the facts," he said Tuesday. "That's what the American people would expect."
Expectations aside, for now at least, Americans are not paying close attention to Syria, says Michael Dimock of Pew Research.
"Even with news recently about the possible use of chemical weapons, there's been no real surge of public interest in the situation," he says. "We're finding fewer than 1 in 5 telling us they're following it very closely, and that's been about the level of interest for the past two years now."
That low level of interest means it's somewhat of a blank slate in terms of defining how Americans look at the situation — creating an opportunity for the White House.
"There's a lot of research and literature over the decades that shows that the way in which a conflict is described has a big bearing on whether the public will support U.S. military intervention there," says Jeremy Rosner, who was on the National Security Council during the Clinton years.
Rosner offers an example: "If it's described mostly as an effort to contain violent behavior by a regime, that tends to draw much more support than for a venture which is meant to create internal change within the country."
That gets to the lessons of Iraq: a war weariness among the public, the difficulty of that mission, and its controversial beginnings and the claims of weapons of mass destruction that were never found.
Dimock says the American public gave President George W. Bush a lot of leeway on limited evidence after the Sept. 11, 2001, attacks.
"In the current environment, the public is a lot more cautious and not as eager to take bold actions on limited information," Dimock says.
Americans will want to know what exactly U.S. involvement would look like. If not boots on the ground — which seems extremely unlikely in Syria — then what the mission, goals and exit strategy are.
Duke University's Peter Feaver, who was on Bush's National Security Council during the Iraq War, says that rather than addressing those questions, he thinks Obama is preparing the public for little or no intervention.
That may suit the public now, "but there's another lesson from public opinion in American foreign policy, and that is the public punishes failure — regardless of whether they supported the policy initially," Feaver says.
While the president meets with national security, military and diplomatic advisers to decide what to do, know too that getting the American public on board is important and will get due consideration as well.